Anyone good with calculus? Please help.

Anyone Good With Calculus? Please Help.

Answers

Answer 1

First take a time derivative of a function describing motion,

[tex]\frac{d}{dt}h(t)=\frac{d}{dt}-4.9t^2+19.6t-14.6=-9.8t+19.6[/tex].

Finding the maxima of the function is obtained by determining where the critical points are. You can find the critical points by equating the derivative with 0 and solving for t,

[tex]\frac{d}{dt}h(t)=0[/tex]

[tex]-9.8t+19.6=0\implies t=\frac{19.6}{9.8}=\boxed{2}[/tex].

So at 2 seconds the ball peaks in height.

To find out the height feed 2 to the function h.

[tex]h(2)=-4.9\cdot2^2+19.6\cdot2-14.6=\boxed{5}[/tex].

So at 2 seconds the ball reaches maximum height of 5 meters.

Hope this helps :)


Related Questions

this khan academy problem confuses me... (5/3)^3= can anyone help me solve it?

Answers

Answer:

4.629

Step-by-step explanation:

(5/3)³5×5×5/3×3×3125/274.629.

Hope it is helpful to you

Zoe has 4 pounds of strawberries to make pies. How many ounces of strawberries Is this?
64 oz.
60 oz.
68 oz.
72 oz.

Answers

Answer: 64 ounces (choice A)

Work Shown:

1 pound = 16 ounces

4*(1 pound) = 4*(16 ounces)

4 pounds = 64 ounces

Solve the equation
P=100x-0.1x^2

Answers

Answer:

100x - 0.01x

Step-by-step explanation:

100x-0.1x^2

100x - 0.01x

1. What is the theoretical probability that the family has two dogs or two cats?
2.
Describe how to use two coins to simulate which two pets the family has.
3. Flip both coins 50 times and record your data in a table
like the one below.
Frequency
Result
Heads, Heads
Heads, Tails
Tails. Heads
Tails. Tails
Total
50
4
Based on your data, what is the experimental probability that the family has two dogs or
two cats?
5
If the family has three pets, what is the theoretical probability that they have three dogs or
three cats?
How could you change the simulation to generate data for three pets
6

Answers

let dogs be heads. Let cats be tails. A coin has two sides, in which you are flipping two of them. Note that there can be the possible outcomes  

h-h, h-t, t-h, t-t.  

How this affects the possibility of two dogs & two cats. Note that there are 1/2 a chance of getting those two (with the others being one of each), which means that out of 4 chances, 2 are allowed.  

2/4 = 1/2  

50% is your answer

Heads represents cats and tails represents dogs. There is two coins because we are checking the probability of two pets. You have to do the experiment to get your set of data, once you get your set of data, you will be able to divide it into the probability for cats or dogs. To change the simulation to generate data for 3 pets, simply add a new coin and category for the new pet.

Hope this helps you out!

Which graph represents y = RootIndex 3 StartRoot x + 6 EndRoot minus 3? in a test plese help fast

Answers

Answer:

Graph (a)

Step-by-step explanation:

Given

[tex]y = \sqrt[3]{x+ 6} -3[/tex]

Required

The graph

First, calculate y, when x = 0

[tex]y = \sqrt[3]{0+ 6} -3[/tex]

[tex]y = \sqrt[3]{6} -3[/tex]

[tex]y = -1.183[/tex]

The above value of y implies that the graph is below the origin when x = 0. Hence, (c) and (d) are incorrect because they are above the origin

Also, only the first graph passes through point (0,-1.183). Hence, graph (a) is correct

Answer:

the answer is A

Step-by-step explanation:

Bill invested $4000 at 6%
compounded annually. Find the
accumulated amount at the end of
12 years.

Answers

Answer:

$ 8048.79

Step-by-step explanation:

P = $4000t = 12 yearsr = 6% = 0.06

Formula:

A = P(1 + r)^t

The total amount:

A = 4000*(1 + 0.06)^12 = 8048.79

We have to find the,

Accumulated amount at end of 12 years.

The formula we use,

→ A = P(1+r)^t

It is given that,

→ P = $4000

→ t = 12 years

Then r will be,

→ 6%

→ 6/100

→ 0.06

Then the total amount is,

→ P(1+r)^t

→ 4000 × (1 + 0.06)^12

→ 8048.79

Thus, $ 8048.79 is the amount.

which of the following is not an asymptote of the hyperbola xy = -42? y = 0 x = 0 y = x

Answers

Given:

The equation of the hyperbola is:

[tex]xy=-42[/tex]

To find:

The the equation which is not an asymptote of the hyperbola.

Solution:

We have,

[tex]xy=-42[/tex]

It can be written as:

[tex]y=\dfrac{-42}{x}[/tex]

Equating denominator and 0, we get

[tex]x=0[/tex]

So, the vertical asymptotic is [tex]x=0[/tex].

The degree of numerator is 0 and the degree of denominator is 1.

Since the degree of numerator is greater that the degree of denominator, therefore the horizontal asymptote is [tex]y=0[/tex] and there is no oblique asymptote.

Therefore, [tex]y=x[/tex] is not an asymptote of the given hyperbola and the correct option is C.

The stem-and-leaf plot above shows house sale prices over the last week in Tacoma. What was the most
expensive house sold? Give your answer in dollars
$

Answers

Answer:

the answer is 2

Step-by-step explanation:

How do I figure this question out

Answers

Answer:

Orthocenter would be in the middle of the shape.

Step-by-step explanation:

B.

how did the tempicher change if at first it increased by 5% and then increased by 20 percent

Answers

Answer:

Increasing a number by 5% and then by 20% is the same as increasing the original number by 26%.

Step-by-step explanation:

Take a number, x.

Now increase it by 5%.

1.05x

Now increase it by 20%.

1.2 * 1.05x = 1.26x

1.26x = 126% of x = 100% of x + 26% of x

100% of x is the same as x, so it is the same as the original x.

The increase is 26% of the original number.

Increasing a number by 5% and then by 20% is the same as increasing the original number by 26%.

Lost-time accidents occur in a company at a mean rate of 0.8 per day. What is the probability that the number of lost-time accidents occurring over a period of 10 days will be no more than 2

Answers

Answer:

0.01375 = 1.375% probability that the number of lost-time accidents occurring over a period of 10 days will be no more than 2.

Step-by-step explanation:

We have the mean during the interval, which means that the Poisson distribution is used.

Poisson distribution:

In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]

In which

x is the number of sucesses

e = 2.71828 is the Euler number

[tex]\mu[/tex] is the mean in the given interval.

Lost-time accidents occur in a company at a mean rate of 0.8 per day.

This means that [tex]\mu = 0.8n[/tex], in which n is the number of days.

10 days:

This means that [tex]n = 10, \mu = 0.8(10) = 8[/tex]

What is the probability that the number of lost-time accidents occurring over a period of 10 days will be no more than 2?

This is:

[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2)[/tex]

In which

[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]

[tex]P(X = 0) = \frac{e^{-8}*8^{0}}{(0)!} = 0.00034[/tex]

[tex]P(X = 1) = \frac{e^{-8}*8^{1}}{(1)!} = 0.00268[/tex]

[tex]P(X = 2) = \frac{e^{-8}*8^{2}}{(2)!} = 0.01073[/tex]

So

[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2) = 0.00034 + 0.00268 + 0.01073 = 0.01375[/tex]

0.01375 = 1.375% probability that the number of lost-time accidents occurring over a period of 10 days will be no more than 2.

A random sample of 64 students at a university showed an average age of 25 years and a sample standard deviation of 2 years. The 98% confidence interval for the true average age of all students in the university is

Answers

Answer:

24.4185<x<25.5815

Step-by-step explanation:

Given the following:

n = 64

mean x = 25

s = 2

z is the z score at 98% CI = 2.326

Get the Confidence Interval:

CI = x±z*s/√n

CI = 25±2.326*2/√64

CI = 25±2.326*2/8

CI = 25±0.5815

CI = (25-0.5815, 25+0.5815)

CI = (24.4185, 25.5815)

CI = 24.4185<x<25.5815

Hence the 98% confidence interval for the true average age of all students in the university is 24.4185<x<25.5815

A box contains 16 large marbles and 18 small marbles. Each marble is either green or white. 9 of the large marbles are green, and 3 of the small marbles are white. If a marble is randomly selected from the box, what is the probability that it is small or green

Answers

Answer:

[tex]P(S&G) =0.7941[/tex]

Step-by-step explanation:

From the question we are told that:

Sample size [tex]n=16+18=>34[/tex]

N0 of  Large [tex]L=16[/tex]

N0 of Small [tex]S=18[/tex]

N0 large Green [tex]L_g=9[/tex]

N0 of small White [tex]S_w=3[/tex]

Therefore

Number of green marbles [tex]N0(G)=9+(18-3)[/tex]

Number of green marbles [tex]N0(G)=24[/tex]

Generally the Number of both small and green Marble is

[tex]N0 of (S&G)= 18 - 3 = 15[/tex]

Generally the  probability that it is small or green P(S&G) is mathematically given by

[tex]P(S&G) = \frac{(18 + 24 - 15)}{(18 + 16)}[/tex]

[tex]P(S&G) =0.7941[/tex]

Complete the sentence that explains why Write an Equation is a reasonable strategy for solving this problem. Because the answer may be _________ the numbers in the problem.

Answers

Answer:

4 e

Step-by-step explanation:

dz6dxrx xrrx6 xz33x4xr4x xrx

Riley wants to make 100ml of 25% saline but only has access to 12% and 38% saline mixtures. x= 12% y=38%

Answers

Answer:

x = 50

y = 50

Step-by-step explanation:

[tex]\begin{bmatrix}x+y=100\\ 0.12x+0.38y=25\end{bmatrix}[/tex]

.12(100-y) + .38y = 25

x = 50

y = 50

Round each of the following numbers to four significant figures and express the result in standard exponential notation: (a) 102.53070, (b) 656.980, (c) 0.008543210, (d) 0.000257870, (e) -0.0357202

Answers

Answer:

Kindly check explanation

Step-by-step explanation:

Rounding each number to 4 significant figures and expressing in standard notation :

(a) 102.53070,

Since the number starts with a non-zero, the 4 digits are counted from the left ;

102.53070 = 102.5 (4 significant figures) = 1.025 * 10^2

(b) 656.980,

Since the number starts with a non-zero, the 4 digits are counted from the left ; the value after the 4th significant value is greater than 5, it is rounded to 1 and added to the significant figure.

656.980 = 657.0 (4 significant figures) = 6.57 * 10^2

(c) 0.008543210,

Since number starts at 0 ; the first significant figure is the first non - zero digit ;

0.008543210 = 0.008543 (4 significant figures) = 8.543 * 10^-3

(d) 0.000257870,

Since number starts at 0 ; the first significant figure is the first non - zero digit ;

0.000257870 = 0.0002579 (4 significant figures) = 2.579 * 10^-4

(e) -0.0357202,

Since number starts at 0 ; the first significant figure is the first non - zero digit ;

-0.0357202 = - 0.03572 (4 significant figures) = - 3.572* 10^-2

use the function to find f(-2) f(x)=[tex]3^{x}[/tex]

Answers

Answer:

[tex] \frac{1}{9} [/tex]

Step-by-step explanation:

[tex]f( - 2) = {3}^{ - 2} [/tex]

[tex]1 \div 9 = .111[/tex]

A graph of 2 functions is shown below. graph of function f of x equals negative 11 by 3 multiplied by x plus 11 by 3 and graph of function g of x equals x cubed plus 2 multiplied by x squared minus x minus 2 Which of the following is a solution for f(x) = g(x)? (2 points) x = −2 x = 1 x = 0 x = −1

Answers

9514 1404 393

Answer:

  (b)  x = 1

Step-by-step explanation:

A graph shows the solution to f(x) = g(x) is x = 1.

__

We want to solve ...

  g(x) -f(x) = 0

  x^3 +2x^2 -x -2 -(-11/3x +11/3) = 0

  x^2(x +2) -1(x +2) +11/3(x -1) = 0 . . . . . factor first terms by grouping

  (x^2 -1)(x +2) +11/3(x -1) = 0 . . . . .  . the difference of squares can be factored

  (x -1)(x +1)(x +2) +(x -1)(11/3) = 0 . . . . we see (x-1) is a common factor

  (x -1)(x^2 +3x +2 +11/3) = 0

The zero product rule tells us this will be true when x-1 = 0, or x = 1.

__

The discriminant of the quadratic factor is ...

  b^2 -4ac = 3^2 -4(1)(17/3) = 9 -68/3 = -41/3

This is less than zero, so any other solutions are complex.

I need all the help I can get. please assist.

4. The equation of a curve is y = (3 - 2x)^3 + 24x.
(a) Find an expression for dy/dx

5. The equation of a curve is y = 54x - (2x - 7)^3.
(a) Find dy/dx​​

Answers

Answer:

4(a).

Expression of dy/dx :

[tex]{ \tt{ \frac{dy}{dx} = - 2(3 - 2x) {}^{2} + 24}}[/tex]

5(a).

[tex]{ \tt{ \frac{dy}{dx} = 54 - 2(2x - 7) {}^{2} }}[/tex]

A Food Marketing Institute found that 34% of households spend more than $125 a week on groceries. Assume the population proportion is 0.34 and a simple random sample of 124 households is selected from the population. What is the probability that the sample proportion of households spending more than $125 a week is less than 0.31

Answers

Answer:

0.2405 = 24.05% probability that the sample proportion of households spending more than $125 a week is less than 0.31.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

Assume the population proportion is 0.34 and a simple random sample of 124 households is selected from the population.

This means that [tex]p = 0.34, n = 124[/tex]

Mean and standard deviation:

[tex]\mu = p = 0.34[/tex]

[tex]s = \sqrt{\frac{0.34*0.66}{124}} = 0.0425[/tex]

What is the probability that the sample proportion of households spending more than $125 a week is less than 0.31?

This is the p-value of Z when X = 0.31, so:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{0.31 - 0.34}{0.0425}[/tex]

[tex]Z = -0.705[/tex]

[tex]Z = -0.705[/tex] has a p-value of 0.2405.

0.2405 = 24.05% probability that the sample proportion of households spending more than $125 a week is less than 0.31.

Solve 8x + c = k for x

Answers

Answer:

x = 1/8(k-c)

Step-by-step explanation:

8x + c = k

Subtract c from each side

8x +c-c = k-c

8x = k-c

Divide each side by 8

8x/8 = (k-c)/8

x = 1/8(k-c)

Answer:

x-1/8(k-c)

Step-by-step explanation:

4 people take 3 hours to paint a fence assume that all people paint at the same rate How long would it take one of these people to paint the same fence?​

Answers

Answer:

12

Step-by-step explanation:

find the slope of the line passing through the points (-4, -7) and (4, 3)

Answers

Answer:

5/4

Step-by-step explanation:

Use the slope formula which is y2-y1/x2-x1.

1. Plug the given values into the equation: 3-(-7)/4-(-4)=5/4

The quadratic equation [tex]x^2+3x+50 = 0[/tex] has roots r and s. Find a quadratic question whose roots are r^2 and s^2.

Answers

According to the question, our quadratic equation is :

\begin{gathered} \bf {x}^{2} - ( {r}^{2} + {s}^{2} )x + {r}^{2} {s}^{2} = 0 \\ \bf \implies \: {x}^{2} - ( - 91)x + {(rs)}^{2} = 0 \\ \bf \implies \: {x}^{2} + 91x + {(50)}^{2} = 0 \\ \bf \implies \: {x}^{2} + 91x + 2500 = 0\end{gathered}

x

2

−(r

2

+s

2

)x+r

2

s

2

=0

⟹x

2

−(−91)x+(rs)

2

=0

⟹x

2

+91x+(50)

2

=0

⟹x

2

+91x+2500=0

After the booster club sold 40 hotdogs at a football game, it had $90 in profit.
After the next game, it had sold a total of 80 hotdogs and had a total of $210
profit. Which equation models the total profit, y, based on the number of
hotdogs sold, X?

Answers

Step-by-step explanation:

x = goods y = $

x Sold = 40, Y = $90

x Sold = 80, Y = $210

sum of xHotdogs = 40+80 = 120 Hotdogs

Sum of Y$ = $90 + 210 = 300

so

X = 2A & Y = 3 its mean one hotdogs can sold for one each = $2.25 and we round it to $3

So = XY = 2A + 3

sorry if i wrong

whats the next two terms in order are p+q, p , p-q

Answers

Answer:

p - 2q and p - 3q

Step-by-step explanation:

A Series is given to us and we need to find the next two terms of the series . The given series to us is ,

[tex]\rm\implies Series = p+q , p , p - q [/tex]

Note that when we subtract the consecutive terms we get the common difference as "-q" .

[tex]\rm\implies Common\ Difference = p - (p + q )= p - p - q =\boxed{\rm q}[/tex]

Therefore the series is Arithmetic Series .

Arithmetic Series:- The series in which a common number is added to obtain the next term of series .

And here the Common difference is -q .

Fourth term :-

[tex]\rm\implies 4th \ term = p - q - q = \boxed{\blue{\rm p - 2q}}[/tex]

Fifth term :-

[tex]\rm\implies 4th \ term = p - 2q - q = \boxed{\blue{\rm p - 3q}}[/tex]

Therefore the next two terms are ( p - 2q) and ( p - 3q ) .

The time it takes a customer service complaint to be settled at a small department store is normally distributed with a mean of 10 minutes and a standard deviation of 3 minutes. Find the probability that a randomly selected complaint takes more than 15 minutes to be settled.

Answers

Answer:

0.0475 = 4.75% probability that a randomly selected complaint takes more than 15 minutes to be settled.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean of 10 minutes and a standard deviation of 3 minutes

This means that [tex]\mu = 10, \sigma = 3[/tex]

Find the probability that a randomly selected complaint takes more than 15 minutes to be settled.

This is 1 subtracted by the p-value of Z when X = 15, so:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{15 - 10}{3}[/tex]

[tex]Z = 1.67[/tex]

[tex]Z = 1.67[/tex] has a p-value of 0.9525.

1 - 0.9525 = 0.0475.

0.0475 = 4.75% probability that a randomly selected complaint takes more than 15 minutes to be settled.

A presidential candidate plans to begin her campaign by visiting the capitals in 3 of 47 states. What is the probability that she selects the route of three specific​ capitals?

Answers

Answer:

1 / 97290

Step-by-step explanation:

The number of ways of selecting 3 specific route capitals from 47 states can be obtained thus :

Probability = required outcome / Total possible outcomes

Total possible outcomes = 47P3

Recall :

nPr = n! / (n-r)!

47P3 = 47! / (47-3)! = 47! / 44! = 97290

Hence, probability of selecting route if 3 specific capitals is = 1 / 97290

13) What is 4 1/2 subtracted from 5.33?
A. 0.43
B. 0.53
C. 0.83
D. 1.08

Answers

Given:

[tex]4\dfrac{1}{2}[/tex] subtracted from 5.33.

To find:

The value for the given statement.

Solution:

[tex]4\dfrac{1}{2}[/tex] subtracted from 5.33 can be written as:

[tex]5.33-4\dfrac{1}{2}[/tex]

On simplification, we get

[tex]=5.33-\dfrac{8+1}{2}[/tex]

[tex]=5.33-\dfrac{9}{2}[/tex]

[tex]=5.33-4.5[/tex]

[tex]=0.83[/tex]

Therefore, the correct option is C.

Ethan buys a video game on sale. If the video game usually costs $60, and it was on sale for 20% off, how much did Ethan pay? Round to the nearest whole dollar.

Answers

Ethan will pay $31.99 with the discount.

How? This is the answer because:

If 39.99 is 100%, and you are trying to find 20%...

1. you need to set it up as a ratio (of course, you do not need to do this, but it is easier for me to do it this way)

2. the ratio will look like this: 39.99/100% x/20%

3. all we need to do from here is to cross multiply!

4 39.99 x

---------- = ----------

100 20

-price is on the top and percent on the bottom

-you would now do 39.99 times 20

-then divide by 100

5. once you have 20% of 39.99, you need to subtract that answer from the total

6. 39.99 - 7.998 = 31.992 (you need to round to the nearest hundredth)

Hope this helps <3

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