Is this a, b, c, or d?

Answer: 2

Step-by-step explanation:2/3 x 6 x 1/2

The integrals for the surface area of the solid obtained by rotating the curves around the specified axes have been set up but not evaluated.

To find the surface area of the solid obtained by rotating the curve y=4xe(⁻⁸ˣ) on the interval 2≤x≤4 about the line x=-3, we can use the formula for surface area of revolution:

S = 2π ∫ [a,b] f(x) √(1+[f'(x)]²) dx

where f(x) is the function being rotated and [a,b] is the interval of rotation.

In this case, we have f(x) = 4xe(⁻⁸ˣ), [a,b] = [2,4], and the axis of rotation is x=-3. To use this formula, we need to first shift the function to the right by 3 units, so that the axis of rotation becomes the y-axis. We can do this by replacing x with x+3 in the function:

f(x) = 4(x+3)e(⁻⁸(ˣ⁺³))

Now, we can use the formula for surface area of revolution about the y-axis:

S = 2π ∫ [a,b] x √(1+[f'(x)]²) dx

where f(x) is the shifted function, f(x) = 4(x+3)e(⁻⁸(ˣ⁺³)), and [a,b] = [-1,1].

To find the surface area of the solid obtained by rotating the curve y=4xe^(⁻³ˣ) on the interval 2≤x≤4 about the line y=-3, we can use a similar approach. This time, we need to shift the function downwards by 3 units, so that the axis of rotation becomes the x-axis. We can do this by replacing y with y+3 in the function:

f(x) = (y+3) / (4e(³ˣ))

Now, we can use the formula for surface area of revolution about the x-axis:

S = 2π ∫ [a,b] y √(1+[f'(y)]²) dy

where f(y) is the shifted function, f(y) = (y+3) / (4e(³y)), and [a,b] = [2,4].

Note that we have set the interval of integration to match the given interval of rotation. However, we have not evaluated the integrals as per the prompt.

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The coordinates that represent the location of P' relative to the center are (28V2, -2872). Therefore, Option B is the correct answer.

Given that point P is rotated 315º counter clockwise around a circle with a diameter of 14 feet.

We are supposed to find which coordinates represent the location of P' relative to the center.

Since the diameter is 14 feet, the radius of the circle is 7 feet, therefore, the center of the circle is the origin (0,0).

We are supposed to find the coordinates of point P', after rotating point P by 315°.

Rotation of a point in the coordinate plane by a rotation angle θ about the origin can be given by the following formulas: x′

=xcosθ−ysinθy′

=xsinθ+ycosθ

Where (x, y) are the coordinates of the point before rotation, and (x′, y′) are the coordinates of the point after rotation.

Substituting the values into the formula we get,

Since P is 7 feet away from the origin in all directions, P is located at (7,0) or (0,7) or (-7,0) or (0,-7).

Hence, the coordinates that represent the location of P' relative to the center are (28V2, -2872).

Therefore, Option B is the correct answer.

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If f is a function from the finite set x to the finite set y, then f is said to be one-to-one if every element in x maps to a unique element in y. In other words, no two elements in x can map to the same element in y.

Now, let's assume that |x|>|y|. This means that there are more elements in x than there are in y. Therefore, there must be at least one element in x that does not have a unique element in y to map to. If this element maps to the same element in y as another element in x, then f is not one-to-one. This is because two elements in x have mapped to the same element in y, violating the definition of a one-to-one function.

Hence, we can conclude that if |x|>|y|, then f cannot be one-to-one. This is a fundamental result in set theory and is important to understand in order to properly define functions and their properties.

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The number of children who swam in the public pool was 304 - 132 = 172.

Let us assume the number of adults who swam in the public pool was x.

Then the number of children would be 304 - x.

We can create an equation from the receipts for admission which totaled $522.00.

The equation can be written as;

2.00x + 1.50(304 - x) = 522.00.

We have the complete solution;

x represents the number of adults who swam in the public pool.

304 - x represents the number of children who swam in the public pool.

The equation that can be written is;

2.00x + 1.50(304 - x) = 522.00

Simplify the equation;

2.00x + 456 - 1.50x = 522.00

0.50x = 66.00

Divide both sides by 0.50;

x = 132

Therefore the number of adults who swam in the public pool was 132.

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The total surface area of the given pyramid is 336ft²

We have.

The surface area of a solid object is a measure of the total area that the surface of the object occupies.

The space occupied by a two-dimensional flat surface is called the area. It is measured in square units. The area occupied by a three-dimensional object by its outer surface is called the surface area.

A surface, as the term is most generally used, is the outermost or uppermost layer of a physical object or space. It is the portion or region of the object that can first be perceived by an observer using the senses of sight and touch, and is the portion with which other materials first interact.

Given is a net of a square pyramid and having dimensions,10 ft 8 ft 12 ft

The total surface area of the pyramid :-

= area of base square +(side)²

= 4 (1/2 x 12 x 8) + 144

= 144+192

= 336ft²

Hence, the total surface area of the given pyramid is 336ft²

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The complete question is :-

The net of a square pyramid and its dimensions are shown in the diagram. 10 ft 8 ft 12 ft What is the lateral surface area of the pyramid in square feet? A 384 ft? B 192 ft? C 160 ft? D 336 ft?​

Molarity: A solution is defined as the number of moles of solute present in 1 liter of the solution. It is represented by Molarity = Number of moles of solute / Volume of solution in Liters.

Given: The solution has 160.0 g of H2SO4 in 0.500 L.
The molarity of the solution can be calculated as follows:
Step 1: Calculate the number of moles of H2SO4 present in the solution:
The molecular mass of H2SO4 = (2 × 1.008) + (1 × 32.06) + (4 × 15.999) = 98.08 g/mol
Number of moles of H2SO4 = Mass of H2SO4 / Molecular mass of H2SO4
= 160.0 g / 98.08 g/mol
= 1.63 mol

Step 2: Calculate the molarity of the solution:
Molarity = Number of moles of solute / Volume of solution in Liters
= 1.63 mol / 0.500 L
= 3.26 M
Therefore, the molarity of the given solution is 3.26 M (Molar).

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The value of 939 dx d939 d 939 (cos x) is cos x by computing first few derivatives and looking for a pattern.

To find 939 dx d939 d 939 (cos x), we need to compute the first few derivatives of cos x and look for a pattern.

The derivative is a key idea in calculus that gauges how quickly a function alters in relation to its input variable. In terms of geometry, the slope of the tangent line to the function graph at a particular location is represented by the derivative. The derivative has numerous crucial uses in mathematics, physics, engineering, and other disciplines, including optimisation, identifying extrema and inflection points, and simulating the rates of change of events that occur in the actual world. The derivative of various functions can be found using a variety of methods, including the power rule, product rule, chain rule, and quotient rule.

The first derivative of cos x is -sin x, the second derivative is -cos x, the third derivative is sin x, and the fourth derivative is cos x. We can notice that the pattern of the derivatives of cos x is that they cycle through the functions cos x, -sin x, -cos x, and sin x.

Since 939 is a multiple of 4 (939/4 = 234.75), we know that the 939th derivative of cos x will be the same as the fourth derivative of cos x, which is cos x.

Therefore, 939 dx d939 d 939 (cos x) = cos x.

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Given, In a group of 300 people, 100 like folk songs, 20% like folk songs but not pop song. if the ratio of people who like pop songs only and do not like both is 3:2. We are to find the number of people who like only one song.

The number of people who like folk songs = 100.We know, that 20% of people like folk songs but not pop songs.So, the number of people who like both folk and pop songs = 20% of 100 = 20.The remaining number of people who like only folk songs = 100 - 20 = 80Let the number of people who like only pop songs be 3xAnd, let the number of people who do not like any song be 2x.

Then, total number of people who like one or the other song = 80 + 20 + 3x + 2x = 100 + 5xWe know, the total number of people = 300Therefore, the number of people who like both folk and pop songs = 300 - (number of people who do not like any song)Therefore, 20 = 300 - 2x5x = 280⇒ x = 56Therefore, the number of people who like only pop songs = 3x = 3 × 56 = 168The number of people who like only one song = 80 + 168 = 248. Hence, the required number of people who like only one song is 248.

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The individual failure rate needs to be approximately 24.5% so that out of 20 users, only 20% fail.

A recent government program required users to sign up for services on a website that had a high failure rate. If each user's chance of failure is independent of another's failure, the individual failure rate needed for out of 20 users, only 20% to fail can be calculated using the binomial probability formula. The formula is P(X=k) = (n choose k) * p^k * (1-p)^(n-k), where n is the number of trials, p is the probability of success, k is the number of successful trials, and (n choose k) is the binomial coefficient.

Here, the number of trials (n) is 20, and the probability of success is 1-p, which is the probability of failure. We want only 20% of users to fail, which means that 80% should succeed. Therefore, p = 0.8. The formula can now be used to find the probability of exactly 16 users succeeding:

P(X=16) = (20 choose 16) * 0.8^16 * (1-0.8)^(20-16)

= 4845 * 0.0112 * 0.0016

= 0.0847

This means that the probability of 16 users succeeding is about 8.47%. To find the individual failure rate, we need to adjust the probability of failure (1-p) so that the probability of exactly 16 users failing is 20%. Let x be the individual failure rate. Then:

P(X=16) = (20 choose 16) * (1-x)^16 * x^4

= 0.2

Solving for x, we get:

x = 0.245

Therefore, the individual failure rate needs to be approximately 24.5% so that out of 20 users, only 20% fail.

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The accuracy of the classification model is 0.918 or 91.8%.

In a classification confusion matrix, the accuracy can be calculated as the sum of the diagonal elements (correct predictions) divided by the sum of all elements (total predictions).

The diagonal elements correspond to the number of true positives (224) and true negatives (3,258), which are correctly classified as 1 and 0, respectively.

The total number of predictions is the sum of all elements in the matrix, which is 3,258 + 28 + 85 + 224 = 3,595.

The accuracy can be calculated as:

accuracy = (true positives + true negatives) / (total predictions)

= (224 + 3,258) / 3,595

= 0.918

The accuracy of a classification confusion matrix may be determined by dividing the entire number of elements (total predictions) by the sum of the diagonal elements (correct predictions).

The number of genuine positives (224) and true negatives (3,258), which are correctly categorised as 1 and 0, respectively, are represented by the diagonal components.

The total number of forecasts is equal to the sum of all matrix elements, which is 3,595 (3,258 + 28 + 85 + 224).

It is possible to determine the accuracy by using the formula accuracy = (true positives + true negatives) / (total predictions) = (224 + 3,258) / 3,595 = 0.918.

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Given the following classification confusion matrix, the accuracy will be 0.9667 or 96.67%

The accuracy can be calculated as (true positives + true negatives) divided by the total number of observations, which is (224 + 3,258) / (224 + 85 + 28 + 3,258) = 0.9667, or 96.67%.

In the given confusion matrix, there are four values: true positives (224), false positives (85), false negatives (28), and true negatives (3,258). True positives represent the number of instances where the model correctly predicted class 1 when the actual class was 1.

True negatives represent the number of instances where the model correctly predicted class 0 when the actual class was 0. The accuracy is the sum of true positives and true negatives divided by the total number of observations, which includes all four values. In this case, the accuracy is 0.9667 or 96.67%.

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The Maclaurin series for f(x) as:

f(x) = ∑[n=0 to ∞] (a_n x^(2n+1) cos(1/7x^2) + b_n x^(2n) sin(1/7x^2))

To obtain the Maclaurin series for the function f(x) = 2x cos(1/7x^2), we first need to find the derivatives of the function at x = 0.

The Maclaurin series is then obtained by summing these derivatives multiplied by appropriate coefficients.

We start by taking the first few derivatives of the function:

f(x) = 2x cos(1/7x^2)

f'(x) = 2 cos(1/7x^2) - 4x^2 sin(1/7x^2)

f''(x) = 28x sin(1/7x^2) - 8 cos(1/7x^2) - 16x^4 cos(1/7x^2)

f'''(x) = -392x^3 cos(1/7x^2) + 56x^2 sin(1/7x^2) + 48x cos(1/7x^2) - 224x^6 sin(1/7x^2)

We can see a pattern emerging here: each derivative involves a combination of sine and cosine terms with increasing powers of x. To simplify the notation, we define:

a_n = (-1)^n (2/7)^(2n+1)

b_n = (-1)^n (2/7)^(2n)

Using these coefficients, we can write the Maclaurin series for f(x) as:

f(x) = ∑[n=0 to ∞] (a_n x^(2n+1) cos(1/7x^2) + b_n x^(2n) sin(1/7x^2))

This series involves both sine and cosine terms, with coefficients that depend on the power of x.

It is worth noting that the coefficients decrease in magnitude as n increases, which means that the series converges rapidly for small values of x.

However, as x becomes large, the terms in the series oscillate rapidly and the series may not converge.

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The amount that Mark should pay for his annual liability insurance premium given the table is $ 1, 946 .

The amount that Mark should pay for his annual liability insurance premium is based on his base rate as a 19 year old .

The formula for the annual liability insurance premium is :

=  ( Rating factor of Age - 2) x Base rate

= ( 3. 80) x 512

= $ 1, 946

In conclusion, the annual liability insurance premium to be paid by Mark who is 19, would be $ 1, 946.

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The width of the path surrounding the garden is 1 meter.

To find the width of the path surrounding the garden, we need to factor the given area expression,[tex]4x^2 + 40x - 44,[/tex] and identify the value of x.
Factor out the greatest common divisor (GCD) of the terms in the expression:
GCD of[tex]4x^2,[/tex] 40x, and -44 is 4.

So, factor out 4:
[tex]4(x^2 + 10x - 11)[/tex]
Factor the quadratic expression inside the parenthesis:
We need to find two numbers that multiply to -11 and add up to 10.

These numbers are 11 and -1.
So, we can factor the expression as:
4(x + 11)(x - 1)
Since we are looking for the width of the path (x), and it's not possible to have a negative width, we can disregard the negative value and use the positive value:
x - 1 = 0
x = 1.

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Therefore, Bryan filled 2 smaller bottles.

Bryan divided 3/4 of a liter of plant fertilizer evenly among some smaller bottles.

He put 3/8 of a liter into each bottle. We need to find how many smaller bottles Bryan filled.

To find the number of smaller bottles filled by Bryan, we need to divide the total amount of fertilizer by the amount in each bottle.

Dividing 3/4 by 3/8 is equivalent to multiplying 3/4 by 8/3:(3/4) × (8/3) = 24/12 = 2

Since 3/4 of a liter was divided evenly among some smaller bottles, and each bottle received 3/8 of a liter, Bryan filled 2 smaller bottles (24/12 = 2).

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The length of the shadow casted by the high rise building is approximately 37.7 feet

The image in the question forms a right triangle:

Angle θ = 57 degrees

Opposite to angle θ = 58 feet

Adjacent to angle θ = x

To solve for x ( length of the shadow casted by the building ), we use the trigonometric ratio.

Note: tangent = opposite / adjacent

Hence:

tan( θ ) = opposite / adjacent

Plug in the values:

tan( 57° ) = 58ft / x

Cross multiply and solve for x:

x × tan( 57° ) = 58ft

x = 58ft / tan( 57° )

x = 37.7 ft

Therefore, the value of x is 37.7 feet.

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If you want to find out if differences exist between thirty car brands on their average miles per gallon. You should perform ANOVA test. The correct answer is B.

To compare the average miles per gallon across thirty car brands, the appropriate test to perform would be ANOVA (Analysis of Variance). ANOVA is used when comparing the means of three or more groups to determine if there are significant differences between them. In this case, you have thirty car brands, which qualify for an ANOVA analysis.

ANOVA (Analysis of Variance) is a statistical test used to compare the means of three or more groups or treatments to determine if there are significant differences between them. It analyzes the variation between the group means and compares it to the variation within the groups.

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As the rate parameter λ increases, the exponential distribution becomes more concentrated around the origin (main answer).

To explain this, recall that the probability density function (PDF) of an exponential distribution is given by f(x) = λe^(-λx) for x ≥ 0. As λ increases, the decay of the function becomes faster.

This means that the likelihood of observing larger values of x decreases, and the distribution becomes more focused around the origin (x = 0). In other words, events are expected to occur more frequently with a higher λ, and the waiting time between events becomes shorter.

This concentration effect is evident in the shape of the exponential distribution's graph, where a larger λ results in a steeper curve, indicating that most of the probability mass is near the origin .

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1. The height of the cone is equal to

2. You can solve for the slant height, s by applying Pythagorean's theorem.

3. To get from the base of the cone to the top of the hill, an ant has to crawl 29 mm.

In Mathematics and Geometry, the volume of a cone can be calculated by using this formula:

Volume of cone, V = 1/3 × πr²h

Where:

By substituting the given parameters into the formula for the volume of a cone, we have the following;

8792 =  1/3 × 3.14 × 20² × h

26,376 =  3.14 × 400 × h

Height, h = 26,376/1,256

Height, h = 21 mm.

Question 2.

In order to solve for the slant height, s, we would have to apply Pythagorean's theorem since the height of the cone has been calculated above.

Question 3.

By applying Pythagorean's theorem, we have the following:

r² + h² = s²

20² + 21² = s²

400 + 441 = s²

s² = 841

Slant height, s = √841

Slant height, s = 29 mm.

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The linear extension of l on s is {(1,3), (2,6), (5,), (1,5), (3,5)}.

The relation | on s = {1,2,3,5,6} means that two elements are related if they have the same parity (i.e., they are both even or both odd).
To find all linear extensions of | on s, we can first write down the pairs that are already related by |:
(1,3), (2,6), (5,)
We can then consider each remaining pair of elements and decide whether they should be related or not in a linear extension of |. For example, we could choose to relate 1 and 5, since they are both odd and do not currently have a relation.
One possible linear extension of | on s is:
{(1,3), (2,6), (5,), (1,5), (3,5)}

Note that there are several other possible linear extensions, depending on which pairs we choose to relate.

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The series ∑(n=1 to infinity) M * n^(-1 - ε) converges by the p-series test, as ε > 0. Therefore, by the Weierstrass M-test, the original series ∑(n=1 to infinity) a_n n^(-z) converges uniformly for Re(z) ≥ 1 + ε.

To show that the series ∑n=1[infinity]ann−z converges uniformly for Rez≥1+ϵ, we need to use the Weierstrass M-test.
First, note that since an is a bounded sequence of complex numbers, there exists a positive constant M such that |an|≤M for all n.
Next, we need to find an expression for |ann−z| that will allow us to bound the series. Since we are choosing the principal branch of n−z, we have |n−z|=n−Rez for Rez≥1. Thus, we have
|ann−z|=|an||n−z|≤M|n−Rez|
Now, we need to find a series Mn such that Mn≥|ann−z| for all n and ∑n=1[infinity]Mn converges. One possible choice is Mn=M/n^2. Then we have
|Mn|=|M/n^2|=M/n^2 and
|Mn−ann−z|=|M/n^2−an(n−Rez)|≥M/n^2−|an||n−Rez|≥M/n^2−M|n−Rez|
Thus, if we choose ϵ>0 such that ϵ<1, then for Rez≥1+ϵ, we have
|Mn−ann−z|≥M/n^2−M(n−1)ϵ≥M/n^2−Mϵ
Now, we can use the Comparison Test to show that ∑n=1[infinity]Mn converges. Since ∑n=1[infinity]M/n^2 converges (p-series with p>1), it follows that ∑n=1[infinity]Mn converges as well.
Thus, by the Weierstrass M-test, we have shown that the series ∑n=1[infinity]ann−z converges uniformly for Rez≥1+ϵ.
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The experimenter is trying to measure the subject's just noticeable difference (JND).

Just noticeable difference (JND) is the smallest detectable difference between two stimuli that a person can detect. In this experiment, the experimenter is presenting the subject with a standard weight of 100 grams and then presenting comparison weights of increasing and decreasing amounts until the subject indicates that the weights are the same.

The just noticeable difference (JND) is an important concept in sensory psychology. It refers to the smallest detectable difference between two stimuli that a person can detect. In this experiment, the experimenter is trying to measure the subject's JND for weight. The experiment involves presenting the subject with a standard weight of 100 grams, followed by a comparison weight of increasing amounts until the subject says that the two weights are the same. The experimenter then repeats this process, but with a comparison weight of decreasing amounts until the subject again says that the two weights are the same.

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We would predict an on-base percentage of approximately .290 for a player with a batting average of .206, assuming average values for walks, hit by pitch, and sacrifice flies.

To predict the on-base percentage (OBP) from a given batting average, we can use the following formula:

OBP = (Hits + Walks + Hit by Pitch) / (At Bats + Walks + Hit by Pitch + Sacrifice Flies)

Since batting average (BA) is defined as Hits / At Bats, we can rearrange this equation to solve for Hits:

Hits = BA * At Bats

Substituting this expression for Hits in the OBP formula, we get:

OBP = (BA * At Bats + Walks + Hit by Pitch) / (At Bats + Walks + Hit by Pitch + Sacrifice Flies)

Now we can plug in the given batting average of .206 and solve for OBP:

OBP = (.206 * At Bats + Walks + Hit by Pitch) / (At Bats + Walks + Hit by Pitch + Sacrifice Flies)

Without more information about the specific player or team, we cannot determine the values of Walks, Hit by Pitch, or Sacrifice Flies. However, we can make a prediction based solely on the batting average. Assuming average values for the other variables, we can estimate a typical OBP for a player with a .206 batting average.

For example, if we assume a player with 500 at-bats (a common benchmark for full seasons), and average values of 50 walks, 5 hit-by-pitches, and 5 sacrifice flies, we can calculate the predicted OBP as follows:

OBP = (.206 * 500 + 50 + 5) / (500 + 50 + 5 + 5)

= (103 + 50 + 5) / 560

= 0.29

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The criterion used to decide on the line that best fits a set of data points is called the "least squares" criterion. Specifically, the criterion states that the line that best fits the data is the one that minimizes the sum of the squared errors between the observed data points and the corresponding predicted values on the line.

The correct answer is b. least-squares.

1. The least squares criterion is a widely used method to determine the line that provides the best fit for a set of data points. It aims to minimize the overall difference between the observed data points and the values predicted by the line.

2. To achieve this, the criterion calculates the error between each observed data point and the corresponding predicted value on the line. The errors are then squared to eliminate the effect of positive and negative differences canceling each other out.

3. The squared errors are summed up, and the line that minimizes this sum of squared errors is considered the best-fitting line. The idea behind this criterion is to find the line that provides the "best compromise" in terms of overall fit to the data.

4. By minimizing the sum of squared errors, the least squares criterion provides a measure of how well the line represents the observed data points. It takes into account both the magnitude and direction of the errors, giving more weight to larger errors. The line with the smallest sum of squared errors is considered the line that best fits the data.

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Answer:

x=42°

Step-by-step explanation:

angles around a point add to 360°

2x+3x+150=360°

take away 150°

2x+3x=210°

5x=210°

divide by 5

x=42°

Answer:

42

Step-by-step explanation:

2x+3x+150°=360°

collect like terms

2x+3x=360°-150°

5x=210°

divide both sides by 5x

therefore, x=42

The expected value of X is 297/35 and the variance of X is 774/1225.

Let's define the indicator random variable Xi as follows:

Xi = 1, if the i-th roll results in a new number (that hasn't been rolled before).

Xi = 0, otherwise.

Then, X is the sum of these indicator variables, that is:

X = X1 + X2 + X3

We know that E[Xi] = 1/p, where p is the probability of rolling a new number on the i-th roll, given that i - 1 distinct numbers have already been rolled. Since there are i - 1 distinct numbers already rolled, the probability of rolling a new number on the i-th roll is (6 - i + 1)/6.

Thus, we have:

E[Xi] = 6/(6-i+1) = 6/(7-i)

Using the linearity of expectation, we can find the expected value of X:

E[X] = E[X1] + E[X2] + E[X3] = 6/7 + 6/6 + 6/5 = 297/35

To find the variance of X, we need to calculate the variance of each Xi:

Var(Xi) = E[Xi^2] - E[Xi]^2

We know that:

E[Xi^2] = 1(6-i+1)/6 + 0(i-1)/6 = (7-i)/6

So, we have:

Var(Xi) = (7-i)/6 - (6/(7-i))^2

Using the linearity of variance, we can find the variance of X:

Var(X) = Var(X1) + Var(X2) + Var(X3)

= (4/6) - (6/7)^2 + (3/6) - (6/6)^2 + (2/6) - (6/5)^2

= 774/1225

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The like terms in the expression 8x² − 4x³ + 5x² × 2x² are 2x².

Like terms are terms with the same variables and the same power of the variables.
In the expression 8x² − 4x³ + 5x² × 2x², the variables are x and the coefficients are 8, −4, and 5 × 2 = 10.
The like terms are the terms that have the same variable raised to the same power.
We can combine these terms as we combine like terms, by adding their coefficients.
The like terms in this expression are:8x² and 5x² × 2x² = 10x² × 2x² = 20x⁴.

The summary is the given terms, 8, -4x³, and 5x² × 2x², are not like terms.

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The derivative of the given function is: f'(x) = sec(5x) / [5(sec(5x) + tan(5x))]

Using the first part of the Fundamental Theorem of Calculus, we can find the derivative of the function f(x) by evaluating its indefinite integral and then differentiating with respect to x.

First, we can evaluate the indefinite integral of the given function as follows:

[tex]\int\limits^x_0 2 sec(5t) dt[/tex]

Using the substitution u = 5t, du/dt = 5, we can simplify this to:

∫₀˵⁰ sec(u) du / 5

= 1/5 ln |sec(u) + tan(u)| from 0 to 5x

= 1/5 ln |sec(5x) + tan(5x)| - 1/5 ln |sec(0) + tan(0)|

= 1/5 ln |sec(5x) + tan(5x)| - 1/5 ln |1 + 0|

= 1/5 ln |sec(5x) + tan(5x)|

Next, we can differentiate this expression with respect to x to find the derivative of f(x):

f'(x) = d/dx [1/5 ln |sec(5x) + tan(5x)|]

= 1/5 (sec(5x) + tan(5x))^-1 * d/dx [sec(5x) + tan(5x)]

= 1/5 (sec(5x) + tan(5x))^-1 * 5sec(5x)

= sec(5x) / [5(sec(5x) + tan(5x))]

Therefore, the derivative of the given function is:

f'(x) = sec(5x) / [5(sec(5x) + tan(5x))]

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The perimeter of the closet is 25.5 ft.

we have the scale

1 unit = 1.5 feet

Then the dimensions of closet are

3 unit = 3 x 1.5 feet = 4.5 ft

4 unit = 4 x 1.5 = 6 ft

4 unit =6  ft

6 unit = 6 x 1.5 = 9 ft

So, the perimeter of the closet

= 4.5 + 6 + 6 + 9

= 25.5 ft

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We have shown that [tex]cov(x_1, x_1) = v(x_1) = \sigma^2_1(x 1 ,x 1 ).[/tex]

To show that [tex]cov(x_1, x_1) = v(x_1) = \sigma^2_1(x 1 ,x 1 )[/tex], we need to first understand what each of these terms means:

[tex]cov(x_1, x_1)[/tex] represents the covariance between the random variable x_1 and itself. In other words, it is the measure of how two instances of x_1 vary together.

v(x_1) represents the variance of x_1. This is a measure of how much x_1 varies on its own, regardless of any other random variable.

[tex]\sigma^2_1(x 1 ,x 1 )[/tex]represents the second moment of x_1. This is the expected value of the squared deviation of x_1 from its mean.

Now, let's show that [tex]cov(x_1, x_1) = v(x_1) = \sigma^2_1(x 1 ,x 1 ):[/tex]

We know that the covariance between any random variable and itself is simply the variance of that random variable. Mathematically, we can write:

[tex]cov(x_1, x_1) = E[(x_1 - E[x_1])^2] - E[x_1 - E[x_1]]^2\\ = E[(x_1 - E[x_1])^2]\\ = v(x_1)[/tex]

Therefore, [tex]cov(x_1, x_1) = v(x_1).[/tex]

Similarly, we know that the variance of a random variable can be expressed as the second moment of that random variable minus the square of its mean. Mathematically, we can write:

[tex]v(x_1) = E[(x_1 - E[x_1])^2]\\ = E[x_1^2 - 2\times x_1\times E[x_1] + E[x_1]^2]\\ = E[x_1^2] - 2\times E[x_1]\times E[x_1] + E[x_1]^2\\ = E[x_1^2] - E[x_1]^2\\ = \sigma^2_1(x 1 ,x 1 )[/tex]

Therefore, [tex]v(x_1) = \sigma^2_1(x 1 ,x 1 ).[/tex]

Thus, we have shown that [tex]cov(x_1, x_1) = v(x_1) = \sigma^2_1(x 1 ,x 1 ).[/tex]

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