formula for permutations with repetition. the number of distinct sequences with n_1 objects of type 1, n_2 objects of type 2, …, n_k objects of type k, where 〖n= n〗_1 n_2 ⋯ n_k is

Answer:

Step-by-step explanation:

Answer: 0.6

Any other answer would be too far away

If it takes 5 seconds to travel and you hear it in 3, then 3/5 equals 0.6

Answer:

0.6 miles

Step-by-step explanation:

5 sec is to 1 mile as 3 sec is to x miles

5/1 = 3/x

5x = 3

x = 3/5 = 0.6

Answer: 0.6 miles

The probability of rolling an odd number given you have spun a red section is 1/3 or approximately 33.33%.

The probability of getting a sum of 7 is 20%.

There are three equally likely outcomes when you spin a red section: roll an odd number, roll an even number, or roll a 1. Of these three outcomes, only one corresponds to rolling an odd number. The probability will be:

= 1/3

= 33.33%

There are 5 possible outcomes when you spin the spinner and 6 possible outcomes when you roll the die, so there are 5 x 6 = 30 equally likely outcomes when you play this game. Therefore, the probability of getting a sum of 7 is 6/30 = 1/5 or 20%.

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In a two population proportions problem, the use of individual proportions for X and Y (i.e., p_x, q_x, and p_y, q_y) is used for confidence intervals instead of the "common p" used in hypothesis testing.

The reason for this is that in hypothesis testing, we are assuming that the two population proportions are equal (i.e., p_x = p_y = p), which means that we can estimate p using the combined sample proportion. However, in a confidence interval problem, we are interested in estimating the difference between the two population proportions, and using the combined sample proportion to estimate p would not be appropriate. Instead, we use the individual sample proportions for X and Y to construct separate confidence intervals for each population proportion, which we can then use to estimate the difference between them.

In other words, when constructing a confidence interval for the difference in proportions, we are interested in estimating the variability of each population proportion separately, and not the variability of the combined sample proportion. This is why we use the individual sample proportions for X and Y in constructing confidence intervals, rather than the common sample proportion used in hypothesis testing.

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To find the indefinite integral of sec(t)(3sec(t)7tan(t))dt, we can start by using the substitution u = sec(t) + tan(t). Then, du/dt = sec(t)tan(t) + sec^2(t), which simplifies to du/dt = u(tan(t) + 1). We can rearrange this equation to get dt = du/u(tan(t) + 1), which allows us to rewrite the original integral as ∫(3u-21)/u^2du. Simplifying this expression, we get 3ln|u| - 21/u + c.

Substituting back in for u and simplifying, our final answer is 3ln|sec(t) + tan(t)| - 21/(sec(t) + tan(t)) + c.


1. Rewrite the integral: ∫(3 sec^2(t) + 7 sec(t)tan(t)) dt.
2. Integrate each term separately:
  a) ∫3 sec^2(t) dt: Since the integral of sec^2(t) is tan(t), we have 3∫sec^2(t) dt = 3tan(t) + C1.
  b) ∫7 sec(t)tan(t) dt: We use substitution method. Let u = sec(t), then du = sec(t)tan(t) dt. So, the integral becomes 7∫u du = (7/2)u^2 + C2 = (7/2)sec^2(t) + C2.
3. Combine both results: 3tan(t) + (7/2)sec^2(t) + C, where C = C1 + C2 is the constant of integration.

So, the general indefinite integral of the given function is 3tan(t) + (7/2)sec^2(t) + C.

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The function represented in the table is:

y = 6*cos(x) + 4

Evaluationg this in x = 45 we will get:

y = 3√2 + 4

Here we have the table of the function:

y = a*cos(x) + b

We can see that when x = 0, y = 10, then:

10 = a*cos(0) + b

10  = a + b

And when x = 90, y = 4, then:

4 = a*cos(90) + b

4 = b

Replacing that value in the equation above:

10 = a + 4

10 - 4 = a

6 = a

Then the function is:

y = 6*cos(x) + 4

Evaluating this in x = 45 we will get:

y = 6*cos(45) + 4

y = 6*√2/2 + 4

y = 3√2 + 4

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The probability the student is in drama, given that they are a sophomore is 23%.

What is probability?

Probability is a way of determining how likely something is to happen. Many events are difficult to predict with total certainty. Using it, we can make predictions about the probability of an event happening, or how likely it is.

Total number of students = 20+7+13+20+13+2+25+5+5 = 100

Number of students in sophomore([tex]S_{o}[/tex]) = 20+7+3 = 30

Number of drama students(D) who are in sophomore = 7

To calculate the probability the student is in drama, given that they are a sophomore:

P(drama | sophomore) = [tex]\frac{P(drama \ and \ sophomore)}{P(sophomore)}[/tex] = 23%

Therefore, probability = [tex]\frac{n(D\cap S_{o} )}{n(S_{o} )} =\frac{7}{30} = 23\%[/tex]

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Answer:x=4

Step-by-step explanation: subtract the 3x from its self then do it to the 5x and then you cross out the 3x's because the cancel out and then your left with 2x-2=6, then you add the 2 to itself which means they cancel out then you add it to the 6 and that gives you 8 then you are left with 2x=8 now you divide the 2x by its self then the 2 cancels out and then 8 divide by 2 is 4 and then x=4

N(5*-26 + *3*)^

que 5* meno 26 + 3 no se puede resolver

We know that the vertex form of a parabola is given.  Therefore, there is no parabola that satisfies these conditions.

y = a(x - h)^2 + k

where (h, k) is the vertex of the parabola and a is a constant that determines the shape of the parabola.

We are given the vertex (5, 25), so we can write:

y = a(x - 5)^2 + 25

We are also given two points on the parabola: (0, 0) and (10, 0). Plugging these into the equation, we get:

0 = a(0 - 5)^2 + 25 => 25 = 25a => a = 1

0 = a(10 - 5)^2 + 25 => 0 = 25a => a = 0

We get two different values for a, which means that the given points do not lie on the same parabola. Therefore, there is no unique solution to this problem.

We can also see this geometrically: the points (0, 0) and (10, 0) lie on the x-axis, which means that the parabola would have to open either upwards or downwards. However, the vertex is above the x-axis, which means that the parabola cannot intersect the x-axis. Therefore, there is no parabola that satisfies these conditions.

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Answer: 19/23

Step-by-step explanation: 4/1=4 16/11=1 5/11 8/7=1 1/7 leaving 19/23 as the only fraction less than one.

The standard error of the sample mean is 1.25.

The formula for the standard error of the sample mean is s/√n, where s is the standard deviation of the sample and n is the sample size. In this case, s=5 and n=16, so the standard error of the sample mean is 5/√16=1.25.

The standard error measures the variability of sample means that could be obtained from the population, and it decreases as the sample size increases. A smaller standard error means that the sample mean is a more precise estimate of the population mean.

In this example, the standard error of 1.25 indicates that the sample mean of 74 is relatively precise, but without additional information, we cannot determine how accurately it estimates the population mean.

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Approximately 23.39% of the underclassmen have an interest in taking a Mandarin course next year.

Option C is the correct answer.

We have,

To determine the percentage of underclassmen interested in taking a Mandarin course, we need to calculate the ratio of the number of underclassmen interested in Mandarin to the total number of underclassmen.

Looking at the two-way frequency table, we can see that there are 145 underclassmen interested in Mandarin out of a total of 620 underclassmen.

To find the percentage, we divide the number of underclassmen interested in Mandarin by the total number of underclassmen and multiply by 100:

= (145 / 620) x 100

= 23.39%

Therefore,

Approximately 23.39% of the underclassmen have an interest in taking a Mandarin course next year.

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The smallest integer value of x that satisfies the inequality 3x+4>=14 is 4.

To find the smallest integer value of x that satisfies the inequality 3x+4>=14, we need to isolate x on one side of the inequality sign.

First, we subtract 4 from both sides of the inequality to get:

3x >= 10

Next, we divide both sides of the inequality by 3 to get:

x >= 10/3

So any value of x that is greater than or equal to 10/3 will satisfy the inequality 3x+4>=14. However, since x is an integer, we need to round up to the smallest integer value that satisfies the inequality.

The smallest integer that is greater than or equal to 10/3 is 4, so the smallest integer value of x that satisfies the inequality is 4.

To check this, we can substitute x=4 back into the original inequality:

3(4) + 4 >= 14

12 + 4 >= 14

16 >= 14

Since 16 is indeed greater than or equal to 14, we have verified that x=4 is a valid solution to the inequality.

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The length of the arc of the curve y=lnx over the interval [1,5] is approximately 43.85 units long.

To find the length of the arc of the curve y=lnx over the interval [1,5], we need to use the arc length formula:

L = [tex]\int_1^5[/tex] √(1+(dy/dx)²) dx

We can find dy/dx by taking the derivative of y=lnx:

y' = 1/x

Then, we can substitute into the formula:

L = [tex]\int_1^5[/tex] √(1+(1/x)²) dx

Using substitution, let x = eⁿ, so dx = eⁿ dt:

L = [tex]\int_1^{ln5}[/tex] √(1+e²ⁿ) eⁿ dt

We can use u-substitution with u=1+e²ⁿ, so du/dt=2e²ⁿ:

L = (1/2)  [tex]\int_1^{26}[/tex] √(u) du

L = (1/2) * (2/3) * ([tex]26^\frac{3}{2}[/tex] - 1)

L = 43.85

Therefore, the length of the arc of the curve y=lnx over the interval [1,5] is approximately 43.85 units long.

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Answer:

the last option

Step-by-step explanation:

The first choice would only target certain customers who come at a very specific time.

the second choice only surveys customers who spend over ten dollars.

The third only surveys muffin eaters!

The last choice has the most unbiased and random sampling to get a sample of all customers.

The probability that it is not raining if the flight leaves on time is 0.9.

Let's define the events:

A: It is raining

B: The flight is delayed

We have,

P(A) = 0.19 (probability that it will rain)

P(B) = 0.1 (probability that the flight will be delayed)

P(A ∩ B) = 0.07 (probability that it will rain and the flight will be delayed)

Using the formula for conditional probability, we have:

P(A' | B') = P(A' ∩ B') / P(B')

Since A' and B' are complementary events (if it's not raining, then the flight is leaving on time), we can rewrite the formula as:

P(A' | B') = P(B' | A') x P(A') / P(B')

We know that P(A) + P(A') = 1, so P(A') = 1 - P(A).

Now, let's substitute the given values into the formula:

P(A' | B') = (P(B' | A') x (1 - P(A))) / P(B')

P(B' | A') represents the probability that the flight is leaving on time given that it's not raining.

We know that:

P(B') = 1 - P(B) = 1 - 0.1 = 0.9

we can estimate P(B' | A') as:

P(B' | A') ≈ P(B') = 0.9

Now we can substitute the values into the formula:

P(A' | B') ≈ (0.9 x (1 - 0.19)) / 0.9

P(A' | B') ≈ 0.81 / 0.9

P(A' | B') ≈ 0.9

Therefore, the probability that it is not raining if the flight leaves on time is 0.9.

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The statement "rxy = 0" represents the null hypothesis in correlation analysis, indicating no linear relationship between variables x and y.

In correlation analysis, the correlation coefficient (r) measures the strength and direction of the linear relationship between two variables, usually denoted as x and y. When the statement "rxy = 0" is made, it refers to the null hypothesis in correlation testing. The null hypothesis states that there is no significant correlation between the variables.

If the correlation coefficient (r) between x and y is found to be exactly 0, it suggests that there is no linear relationship between the variables. This means that changes in x are not associated with any predictable changes in y.

Researchers use statistical tests, such as hypothesis testing, to evaluate whether the observed correlation coefficient is significantly different from 0. If the calculated correlation coefficient is significantly different from 0, the null hypothesis is rejected, indicating evidence of a linear relationship between x and y. However, if the calculated correlation coefficient is close to 0, it supports the null hypothesis, suggesting no linear relationship between the variables.


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Answer:

Step-by-step explanation:

Yes, the Student Council advisor's sample method is valid.

In this scenario, the sample method used by the Student Council advisor is known as systematic sampling. The process of selecting every nth element from a population is known as systematic sampling. The advisor in this case polled every tenth student in the lunch line. This method is valid because it guarantees that every student in the population has an equal chance of being chosen and provides a representative sample of the entire student body.

The advisor obtained a sample distribution of their preferred contact methods for school news by surveying 36 students. The advisor discovered that 16 students preferred email, 12 preferred newsletters, 5 preferred announcements, and 3 preferred phone contact from this sample. The proportion of students in the sample who preferred email can be used to estimate the number of students who prefer email among the entire student population.

In this case, 16 of 36 students preferred email, representing 44.44 percent (16/36 * 100). We can estimate the number of students who prefer email by applying this percentage to the total student population if we assume that this proportion remains constant across the entire student population. Given that the school has 684 students, we can expect approximately 303 students (684 * 44.44 percent) to prefer email as their preferred method of communication for school news.

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Answer:

[tex] \frac{ {6}^{2} }{ {15}^{2} } = \frac{36}{225} = .16 = 16\%[/tex]

The side which must have the same length as BC is RS.

The correct answer choice is option C.

Given the figure ABCD with a similar figure QRST

If AD = 12 and QT = 12

AB = 8 and QR = 8

Then,

BC = RS

and

CD = ST

Hence, the side corresponding to BC is RS

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The Fourier series for the function f(x) = { -1, -1 ≤ x < 0; 1, 0 ≤ x ≤ 1 } in the interval [−1, 1] is (4/π) ∑n=1∞ [sin((2n−1)πx)/(2n−1)]. This represents an odd function and is known as a Fourier sine series.

The Fourier series for the function f(x) = { −1, −1 ≤x < 0; 1, 0 ≤x ≤1 } in the interval [−1, 1] can be expressed as follows:

f(x) = ∑n=0∞ (a0/2 + an cos(nπx) + bn sin(nπx))

where a0, an, and bn are the Fourier coefficients, given by:

a0 = (1/2) ∫−1^1 f(x) dx = 0

an = (1/π) ∫−1^1 f(x) cos(nπx) dx = 2(1−cos(nπ))/nπ

bn = (1/π) ∫−1^1 f(x) sin(nπx) dx = 0

Therefore, the Fourier series for f(x) in the interval [−1, 1] is:

f(x) = ∑n=1∞ [2(1−cos(nπ))/nπ] sin(nπx)

This series can also be written as:

f(x) = (4/π) ∑n=1∞ [sin((2n−1)πx)/(2n−1)]

This is an example of a Fourier sine series since the function f(x) is odd (i.e., f(−x) = −f(x)).

In summary, the Fourier series for f(x) = { −1, −1 ≤x < 0; 1, 0 ≤x ≤1 } in the interval [−1, 1] is given by:

f(x) = (4/π) ∑n=1∞ [sin((2n−1)πx)/(2n−1)]

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To calculate the standard deviation of hypothetical hours of television watched by high school students per week, we need to use the formula for standard deviation with the given set of numbers.

The standard deviation is a measure of the spread of data around the mean. To calculate the standard deviation of the hypothetical hours of television watched by high school students per week, we need to first determine the mean of the data. Let's say the data set is {10, 8, 12, 6, 14, 10, 8, 16}. The mean is found by adding up all the numbers and dividing by the total number of numbers, which in this case is 10. The sum of the numbers is 84, so the mean is 8.4.

Next, we need to calculate the deviation of each number from the mean. This is done by subtracting the mean from each number. For example, the deviation of the first number (10) is 10 - 8.4 = 1.6. The deviation of the second number (8) is 8 - 8.4 = -0.4 (note that negative deviations indicate values below the mean).

Then, we square each deviation and add up all the squared deviations. This gives us the sum of squared deviations, which is 40.8 for this data set.

Finally, we divide the sum of squared deviations by the total number of numbers minus one, and then take the square root of this value. In this case, the calculation would be:

sqrt(40.8 / (10 - 1)) = 2.31

So the standard deviation of the hypothetical hours of television watched by high school students per week is 2.31 hours. This means that the data is relatively tightly clustered around the mean of 8.4 hours, with most values falling within 2.31 hours of the mean.

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The statements that are always true regarding the diagram of interior and exterior angles of a triangle include the following:

C. m∠5 + m∠6 =180°.

D. m∠2 + m∠3 = m∠6.

E. m∠2 + m∠3 + m∠5 = 180°.

In Mathematics and Geometry, the exterior angle property can be defined as a theorem which states that the measure of an exterior angle in a triangle is equal in magnitude to the sum of the measures of the two remote or opposite interior angles of that triangle:

m∠2 + m∠3 = m∠6.

According to the Linear Pair Postulate which states that the measure of two (2) angles would add up to 180° provided that they both form a linear pair, we have:

m∠5 + m∠6 =180°.

As a general rule in geometry, the sum of all the angles that are formed by a triangle is equal to 180º and this gives:

m∠2 + m∠3 + m∠5 = 180°.

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Missing information:

The question is incomplete and the complete question is shown in the attached picture.

The surface area of the two rectangular prisms is S = 2 ( 2B + ph )

Given data ,

Surface Area of the prism = 2B + ph

The area of the triangular prism is A = ph + ( 1/2 ) bh

Now , ice cube is cut horizontally into two smaller rectangles prisms

where the length of the prism is l and width is w , and height is h

On simplifying , we get

The surface area of 2 prisms is S = 2 ( 2B + ph )

where B = base area of prism = l x w

And , p = perimeter of prism

h = height of prism

Hence , the surface area is S = 2 ( 2B + ph )

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The box plot that represents the data is the third option.

A box plot is a graph that is used to study the distribution and level of a set of scores. The box plot consists of two lines and a box. the two lines are known as whiskers.

The first whisker represents the minimum number and the end of the second whisker represents the maximum number. On the box, the first line to the left represents the lower quartile. The next line on the box represents the median. The third line on the box represents the upper quartile.

The numbers arranged in ascending order : 64, 68, 68, 74, 76, 82, 84, 86, 90, 90, 92,  94,

The minimum number is 64 and the maximum number is 94.

First quartile = 1/4(n + 1)

1/4 x (12 + 1) = 3.25 number = 71

Third quartile =  3/4(n + 1)

3/4 x (12 + 1) = 9.75 number = 90

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The sampling method described in which the population is first divided into groups and then random samples are drawn from each group is called stratified sampling. In this sampling method, the population is divided into homogeneous subgroups called strata, based on some characteristic of interest such as age, gender, income level, or geographic location. Random samples are then drawn from each stratum, and the data collected from each sample are combined to form the final sample.

Stratified sampling is often used when the population is heterogeneous, meaning that it has distinct subgroups with different characteristics that may affect the outcome of the study. By dividing the population into homogeneous subgroups, stratified sampling increases the precision of the estimates and reduces the sampling error, compared to simple random sampling. Stratified sampling also ensures that each subgroup of the population is represented in the sample, which may be important for making inferences about the entire population. However, stratified sampling can be more complex and time-consuming than simple random sampling, especially if the population has many subgroups.

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The volume of the solid is 80 cubic units.

The given double integral is:

∫ ∫ r 2 x d a

where r = { ( x , y ) ∣ 0 ≤ x ≤ 4 , 0 ≤ y ≤ 5 }

We can identify the integrand 2x as the area of a rectangular strip of thickness dx along the x-axis, with width 2x and height y, located at a distance x from the y-axis. Therefore, the double integral represents the volume of the solid obtained by stacking such rectangular strips over the region r.

To find the volume, we integrate the area of each rectangular strip over the interval 0 ≤ y ≤ 5 and then sum up the volumes of all such strips over the interval 0 ≤ x ≤ 4. Hence, we have:

∫ ∫ r 2 x d a = ∫ 0 4 ∫ 0 5 2x dy d

= ∫ 0 4 [2x(y)|0⁵] dx

= ∫ 0 4 10x dx

= [5x²|0⁴]

= 80

Therefore, the volume of the solid is 80 cubic units.

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6 × 3,725 is equivalent to the value of 22,350.

We have,

To find the value of 6 × 3,725, we multiply the number 6 by the number 3,725.

This can be done by adding 3,725 to itself 6 times or by adding 6 to itself 3,725 times.

However, it is more efficient to use the multiplication operation, which is a shorthand way of adding a number to itself multiple times.

Using the multiplication operation, we can write 6 × 3,725 as:

6 × 3,725 = 6 × (3,000 + 700 + 20 + 5)

= (6 × 3,000) + (6 × 700) + (6 × 20) + (6 × 5)

= 18,000 + 4,200 + 120 + 30

= 22,350

Therefore,

6 × 3,725 is equivalent to the value of 22,350.

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Answer:  [tex]\frac{-3}{10}[/tex]

Given:

   (b + d) - a

Substitute known values:

   ([tex]\frac{3}{5}[/tex] + - [tex]\frac{1}{5}[/tex]) - [tex]\frac{7}{10}[/tex]

Addition and subtraction becomes subtraction:

   ([tex]\frac{3}{5}[/tex] - [tex]\frac{1}{5}[/tex]) - [tex]\frac{7}{10}[/tex]

Subtract:

   [tex]\frac{2}{5}[/tex] - [tex]\frac{7}{10}[/tex]

Common denominators:

   [tex]\frac{4}{10}[/tex] - [tex]\frac{7}{10}[/tex]

Subtract:

   [tex]\frac{-3}{10}[/tex]

Using the substitution method and the given information, we can evaluate ∫50f(5x)dx as 4.

We can use the substitution method to evaluate the integral ∫50f(5x)dx. Let u = 5x, then du/dx = 5 and dx = du/5. Substituting these expressions into the integral, we get:

∫50f(5x)dx = ∫10f(u) du/5

Next, we can apply the constant multiple rule for integrals, which states that ∫a kf(x)dx = k ∫a f(x)dx for any constant k. Using this rule, we can move the constant factor 1/5 outside the integral:

∫50f(5x)dx = (1/5) ∫10f(u) du

Now, we can use the given information that ∫250f(x)dx = 20 to find a relationship between ∫10f(u) du and ∫250f(x)dx. Substituting u = 5x into the bounds of integration, we get:

∫50f(5x)dx = (1/5) ∫250f(u) du, evaluated from u = 50 to u = 250

Using the Fundamental Theorem of Calculus, we can evaluate the definite integral ∫250f(u) du as follows:

∫250f(u) du = F(250) - F(50)

where F(x) is an antiderivative of f(x). Since f(x) is continuous, it has an antiderivative F(x). We are given that ∫250f(x)dx = 20, so we can write:

F(250) - F(50) = ∫250f(x)dx = 20

Simplifying, we get:

F(250) = F(50) + 20

Now we can substitute this relationship back into our expression for ∫50f(5x)dx:

∫50f(5x)dx = (1/5) ∫250f(u) du, evaluated from u = 50 to u = 250
              = (1/5) [F(250) - F(50)]
              = (1/5) [F(50) + 20 - F(50)]
              = 4

Therefore, we have found that:

∫50f(5x)dx = 4

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The curve given by the equation y = x(t^2/t^2 + t + 9) dt on the interval [0,∞) is concave downward on the interval [3, ∞).

To find where the curve is concave downward, we need to take the second derivative of the function and check where it is negative. Taking the second derivative of the given function with respect to x, we get:

y'' = 2t^2(t^2 + 18)/[(t^2 + t + 9)^3]

To find where y'' is negative, we need to solve the inequality 2t^2(t^2 + 18)/[(t^2 + t + 9)^3] < 0. Factoring the numerator, we get:

2t^2(t^2 + 18) = 2t^2(t+√18)(t-√18)

This is negative when t is between -√18 and 0, and also when t is between 0 and √18. However, we need to consider the interval [0,∞) only, which means we should take the solution from the interval [0, √18]. Therefore, the curve is concave downward on the interval [3, ∞).

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