(2 pts.) 9.) Find two equivalent expressions to tan 20° using the cotangent function in degrees.

Solve these linear equations in the form y=yn+yp with yn=y(0)e^at.

WINSTONCH [101]

Answer:

a) $y(t) = y_{0}e^{4t} + 2$ . It does not have a steady state

b) $y(t) = y_{0}e^{-4t} + 2$ . It has a steady state.

Step-by-step explanation:

a) $y' -4y = -8$

The first step is finding $y_{n}(t)$ . So:

$y' - 4y = 0$

We have to find the eigenvalues of this differential equation, which are the roots of this equation:

$r - 4 = 0$

$r = 4$

So:

$y_{n}(t) = y_{0}e^{4t}$

Since this differential equation has a positive eigenvalue, it does not have a steady state.

Now as for the particular solution.

Since the differential equation is equaled to a constant, the particular solution is going to have the following format:

$y_{p}(t) = C$

So

$(y_{p})' -4(y_{p}) = -8$

$(C)' - 4C = -8$

C is a constant, so (C)' = 0.

$-4C = -8$

$4C = 8$

$C = 2$

The solution in the form is

$y(t) = y_{n}(t) + y_{p}(t)$

$y(t) = y_{0}e^{4t} + 2$

b) $y' +4y = 8$

The first step is finding $y_{n}(t)$ . So:

$y' + 4y = 0$

We have to find the eigenvalues of this differential equation, which are the roots of this equation:

$r + 4 =$

$r = -4$

So:

$y_{n}(t) = y_{0}e^{-4t}$

Since this differential equation does not have a positive eigenvalue, it has a steady state.

Now as for the particular solution.

Since the differential equation is equaled to a constant, the particular solution is going to have the following format:

$y_{p}(t) = C$

So

$(y_{p})' +4(y_{p}) = 8$

$(C)' + 4C = 8$

C is a constant, so (C)' = 0.

$4C = 8$

$C = 2$

The solution in the form is

$y(t) = y_{n}(t) + y_{p}(t)$

$y(t) = y_{0}e^{-4t} + 2$

6 0

3 years ago

In the center of town there is a square park with an area of 900 square feet. If Stephen walks from one corner of the park to th

Vedmedyk [2.9K]

The distance walked by Stephen is 42.42 feet

<h3>Solution:</h3>

Given that In the center of town there is a square park with an area of 900 square feet

Stephen walks from one corner of the park to the opposite corner

To find: Distance walked by Stephen

We need to find the distance that the person walk from one corner of the park to the opposite corner.

So, we need to find the Diagonal of the square park

The diagonal of square is given as:

$\text{ Diagonal } = \sqrt{2} \times \text{ side}$

Let us find the length of side of square

Given area of square = 900 square feet

The area of square is given as:

$area = (side)^2\\\\900 = (side)^2$

Taking square root on both sides,

$side = \sqrt{900} \\\\side = 30$

Thus length of each side of square is 30 feet

Therefore, length of diagonal is given as:

$diagonal = \sqrt{2} \times 30\\\\diagonal = 1.414 \times 30 = 42.42$

Hence, the distance that the person walks 42.42 feet

3 0

3 years ago

Ellie has 5/8 of a cup of powdered sugar. She sprinkles 3/10 of the sugar onto a plate of

Klio2033 [76]

Answer:

She sprinkles 3/10 of a cup of powdered sugar on the brownies.

Step-by-step explanation:

4 0

2 years ago

What is Best Buy out of 3 lbs for 1.89 or 5lbs for 2.49

vodomira [7]

1.89 / 3 = 0.63 per pound
2.49/ 5 = 0.498 per pound

answer
5lbs for 2.49 is the best buy

8 0

3 years ago

Read 2 more answers

A round wading pool has a diameter of 115cm deep. A hose is filling the pool at a rate of 34000cm^3, cubed per minute. How long

inn [45]

Answer:

It will take 6.118 minutes to fill up the pool to a depth of 20 cm

Step-by-step explanation:

The first step is to calculate the volume of the wading pool.

we will assume it is a cylinder, hence the volume will be = $\pi r^{2}h$

Where r= radius of the pool = 115/2 = 57.5cm

h = depth of the pool =20 cm

The volume of the pool will be $\pi \times57.5^{2} \times 20 =2.08 \times 10^{5} cm ^{3}$

We are filling a pool of 208,000cm ^{3} at the rate of 34000cm^3, cubed per minute.

To get the time it will take to fill up the pool, we will have to divide as follows:

208,000cm ^{3} / 34000cm^3 =6.118 minutes

Therefore it will take 6.118 minutes to fill up the pool to a depth of 20 cm

4 0

3 years ago