For the function f(x) = 1/4e^-x + e^x, prove that the arc length on any interval has the same value as the area under the curve.

Answers

Answer 1

Take an arbitrary interval [a, b], where a < b.

Compute the arc length L of y = f(x) over [a, b] :

[tex]L=\displaystyle\int_a^b\sqrt{1+\left(f'(x)\right)^2}\,\mathrm dx[/tex]

Now comptue the area A under the curve y = f(x) over [a, b] :

[tex]A=\displaystyle\int_a^bf(x)\,\mathrm dx[/tex]

We have

f (x) = 1/4 e ⁻ˣ + e ˣ   →   f ' (x) = -1/4 e ⁻ˣ + e ˣ

Then

√(1 + (f ' (x))²) = √(1 + (-1/4 e ⁻ˣ + e ˣ)²)

… = √(1 + 1/16 e ⁻²ˣ - 1/2 + e ²ˣ)

… = √(1/16 e ⁻²ˣ + 1/2 + e ²ˣ)

… = 1/4 √(e ⁻²ˣ + 8 + 16e ²ˣ)

… = 1/4 √((e ⁻ˣ + 4 e ˣ)²)

… = 1/4 (e ⁻ˣ + 4 e ˣ)

… = 1/4 e ⁻ˣ + e ˣ

… = f (x)

so both A = L for any choice of interval [a, b].

Answer 2

It is true that the arc length on any interval has the same value as the area under the curve.

How to prove the statement

The function is given as:

[tex]f(x) = \frac 14e^{-x} + e^x[/tex]

Differentiate the function

[tex]f'(x) = -\frac 14e^{-x} + e^x[/tex]

On any interval, the following must be true

[tex]f(x) =f'(x)[/tex]

and

[tex]f(x) = \sqrt{1 + (f'(x))^2}[/tex]

So, we have:

[tex]f(x) = \sqrt{1 + (-\frac 14e^{-x} + e^x)^2}[/tex]

Expand the exponents

[tex]f(x) = \sqrt{1 + (\frac{1}{16}e^{-2x} - \frac 12 + e^{2x})}[/tex]

Remove the bracket

[tex]f(x) = \sqrt{1 + \frac{1}{16}e^{-2x} - \frac 12 + e^{2x}}[/tex]

Evaluate the like terms

[tex]f(x) = \sqrt{\frac{1}{16}e^{-2x} + \frac 12 + e^{2x}}[/tex]

Multiply by 16/16

[tex]f(x) = \sqrt{\frac{16}{16}(\frac{1}{16}e^{-2x} + \frac 12 + e^{2x})}[/tex]

So, we have:

[tex]f(x) = \sqrt{\frac{1}{16}(e^{-2x} + 8 + 16e^{2x})}[/tex]

Take the square root of 1/16

[tex]f(x) = \frac{1}{4}\sqrt{e^{-2x} + 8 + 16e^{2x}}[/tex]

Express the radical as a perfect square

[tex]f(x) = \frac{1}{4}\sqrt{(e^{-x} + 4e^{x})^2}[/tex]

Evaluate the exponents

[tex]f(x) = \frac{1}{4} * (e^{-x} + 4e^{x})[/tex]

Evaluate the products

[tex]f(x) = \frac{1}{4}e^{-x} + e^{x}[/tex]

Hence, it has been proved that  the arc length on any interval has the same value as the area under the curve.

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Varies

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Y= 250x+45

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C

Step-by-step explanation:

don't ask why, i used the goegebra app, and wrote each one in it

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Answers

Answer:

$1050

Step-by-step explanation:

I = PRT / 100

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Solve and graph 4<-1/3n

Answers

Answer:

n<-12

Step-by-step explanation:

4<-1/3n

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Find the area of the composite figure.
Round to the nearest hundredth.
(10 Points)
20.9m
14.3m
22.7 m

Answers

Answer:

474.43 m²

Step-by-step explanation:

The shape is composed of a rectangle and a parallelogram

Area of the composite shape = area of the rectangle + area of the parallelogram

= Length*Width + base*height

Where,

Length = 20.9 m

Width = 14.3 m

base = 20.9 m

height = 22.7 - 14.3 = 8.4 m

Area = 20.9*14.3 + 20.9*8.4

Area = 298.87 + 175.56

= 474.43 m²

Read the description of a proportional relationship.
Ezra is finding the perimeter of different-sized regular pentagons. There is a proportional relationship between the side length of the regular pentagon in inches, x, and the perimeter of the regular pentagon in inches, y.
A regular pentagon with 1-inch side lengths has a perimeter of 5 inches. Write the equation for the relationship between x and y.
y=

Answers

Answer:

Step-by-step explanation:

The answer is 15

the equation for the relationship between x and y is,

y = 5x

What is perimeter?

A perimeter is a closed path that encompasses, surrounds, or outlines either a two dimensional shape or a one-dimensional length. The perimeter of a circle or an ellipse is called its circumference. Calculating the perimeter has several practical applications.

Perimeter refers to the total outside length of an object,

The equation given in the problem is

y = 5x

where

the side length of the regular pentagon in inches, x,

the perimeter of the regular pentagon in inches, y

Hence, the equation for the relationship between x and y is,

y = 5x

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What is the m
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Answers

9514 1404 393

Answer:

  27

Step-by-step explanation:

The measure of an inscribed angle is half the measure of the arc it subtends.

  ∠P = (RT)/2

  ∠P = 54/2

  ∠P = 27

Estimate 85.77-62.396 by first rounding each number to the nearest whole number

Answers

Answer:

24

Step-by-step explanation:

85.77-62.396 estimated by rounding each number to the nearest whole number is 24. I got this by first rounding 85.77 to 86. I then rounded 62.396 to 62. Next, I did 86-62= 24.

So, the answer is 24.

Answer:

23.000

Step-by-step explanation:

8-6=2

5-2=3

So you know that 23.000 is the roaded answer, you can just ignore the digits behind the decimal point in order to round

Vending machines can be adjusted to reject coins above and below certain weights. The weights of legal U.S. quarters have a normal distribution with a mean of 5.67 grams and a standard deviation of 0.07 gram. If a vending machine is adjusted to reject quarters that weigh more than 5.81 grams and less than 5.53 grams, what percentage of legal quarters will be rejected by the vending machine

Answers

Answer: The percentage of legal quarters will be rejected by the vending machine = 2.275%

Step-by-step explanation:

Given: The weights of legal U.S. quarters have a normal distribution with a mean of 5.67 grams and a standard deviation of 0.07 gram.

Let x be the weights of legal U.S. quarters .

Required probability: [tex]P(x<5.53)+P(x>5.81)[/tex]

[tex]=P(\dfrac{x-\mu}{\sigma}<\dfrac{5.33-5.67}{0.07})+P(\dfrac{x-\mu}{\sigma}>\dfrac{5.81-5.67}{0.07})\\\\=P(z<-4.857)+P(z>2)\approx0.02275 \ \ \ [By\ P-value\ calculator][/tex]

The percentage of legal quarters will be rejected by the vending machine = 2.275%

Please help.
You will get brainliest.

Answers

Answer:

a

Step-by-step explanation:

1.what is the place value of 3 in 17.32
2.write as decimal 6+4/10​

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Answers
1. Tenth
2. 6.4

Answer:

1. Tenth.

2. 6+ 0.4=6.4.

Evaluate 2x3 - 3x2 + 4 for x = - 2.​

Answers

The correct answer is-24

Answer:

0 or 1.110838652

Step-by-step explanation:

The monthly cost for 46 minutes of calls is 12.75. What is the monthly cost for 52 minutes of calls?

Answers

Answer:

$14.41

Step-by-step explanation:

set up a proportion then cross-multiply:

12.75 / 46 = x / 52

46x = 663

x = 14.41

I'm ABC, the measure of

Answers

Answer: D,E,F,G

It's self explanitory

Answer:

I would say an angle.

Step-by-step explanation:

Three people take 2 1⁄2( two and a half ) hours to deliver leaflets to 270 houses

Assuming all people deliver leaflets at the same rate, how long will it take five people to deliver leaflets to 450 houses?
Give your answer in hours and minutes

Answers

9514 1404 393

Answer:

  2 hours 30 minutes

Step-by-step explanation:

Effort is measured in people-hours per house. Here, the effort to deliver one leaflet is ...

  (3 people)(2.5 hours)/(270 houses) = 1/36 people-hours/house

Then the number of hours (h) for 5 people and 450 houses is ...

  (5 people)(h hours)/(450 houses) = 1/36 people-hours/house

  h = (1/36)(450/5) = 2.5

It will take 2 hours 30 minutes to deliver to 450 houses.

_____

Alternate solution

The time is (assumed) inversely proportional to the number of people, so increasing the number of people from 3 to 5 multiplies the time by 3/5. The time is proportional to the number of houses, so increasing the number of houses from 270 to 450 multiplies the time by 450/270 = 5/3. The time for the second task is (3/5)(5/3) = 1 times the time for the first task.

2 1/2 hours is 2 hours 30 minutes.

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Answer:

1:15 P.M

Step-by-step explanation:

After 5 hours if will be 1:00 P.M and 25 minutes after it turns 1:00 P.M will be 1:15 P.M

Answer:

1 : 15p.m

Step-by-step explanation:

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Rearrange the parts of the parallelogram to form a rectangle. Find the area of ​​the parallelogram and the area of ​​the rectangle. How are the areas related?

Make a copy of the trapezoid to form a parallelogram. Find the area of ​​the trapezoid and the area of ​​the parallelogram. How are the two areas related?

Answers

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Answers

Answer:C

Step-by-step explanation:

The expression that most adequately expresses the model would be:

C). 3 × 2/5

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A fraction is described as an expression employed to denote a segment or section belonging to a larger whole.

In the given question, it can be observed that the model contains 10 parts in total with a division of 5 each into 2 parts.

Since the division of 2 is made thrice, it gives 3 × 2/5 which makes the third option the correct one.

Thus, option C is the correct answer.

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Answer:

$3467 - $1213.45 (35%)

B

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Answer:

Third option

Step-by-step explanation:

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Answers

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Step-by-step explanation:

triangle: [(4 1/2) x 5] / 2

11.25

semicircle: (5/2)^2 x 3.14

(2.5^2 x 3.14) / 2

(6.25 x 3.14) / 2

19.625 / 2

9.8125

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rounded: 21.1

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Answers

Answer:

Simplified ratio is 9:16

Step-by-step explanation:

I WILL MARK YOU AS BRAINLIEST IF YOU ARE CORRECT! THIS QUESTION IS SUPER EASY! Look at the image below.

Answers

Answer:

the answer you are looking for is B

Answer:

A

Step-by-step explanation:

Its A.....unless im super dum lol

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The answer is perpendicular :]

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wont waste your time

I need the volume asap please homework due in 10mins question is a sphere has the inside of it a 9 so what's the volume ​

Answers

Answer:

Step-by-step explanation:

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Solve the equation for all real solutions in simplest form.
-3w^2-10w+1=\,\,-4w^2−4w 2

Answers

Here is the answer. Let me know if you need any clarification!

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