Answer:
The volume of the solid is 
Step-by-step explanation:
In this case, the washer method seems to be easier and thus, it is the one I will use.
Since the rotation is around the y-axis we need to change de dependency of our variables to have
. Thus, our functions with
as independent variable are:
For the washer method, we need to find the area function, which is given by:
![A=\pi\cdot [(\rm{outer\ radius)^2 -(\rm{inner\ radius)^2 ]](https://tex.z-dn.net/?f=A%3D%5Cpi%5Ccdot%20%5B%28%5Crm%7Bouter%5C%20radius%29%5E2%20-%28%5Crm%7Binner%5C%20radius%29%5E2%20%5D)
By taking a look at the plot I attached, one can easily see that for a rotation around the y-axis the outer radius is given by the function
and the inner one by
. Thus, the area function is:
![A(y)=\pi\cdot [(\sqrt{y} )^2-(y^2)^2]\\A(y)=\pi\cdot (y-y^4)](https://tex.z-dn.net/?f=A%28y%29%3D%5Cpi%5Ccdot%20%5B%28%5Csqrt%7By%7D%20%29%5E2-%28y%5E2%29%5E2%5D%5C%5CA%28y%29%3D%5Cpi%5Ccdot%20%28y-y%5E4%29)
Now we just need to integrate. The integration limits are easy to find by just solving the equation
, which has two solutions
and
. These are then, our integration limits.

Answer: 3x+4=5x
Step-by-step explanation:
Three times a number: 3x
Increased by 4 then means that you are adding 4 to that number after it is multiplied: 3x+4
Is equal to 5 times the number means that you have to set the equation equal to 5x: 3x+4=5x
Answer:
1056 feet per a minute
Step-by-step explanation:
math
He has 13 kids in his class. I subtracted 42 - 3 and got 39. Then I divided 39 by 3. That gave me 13.
Answer:
By the end of the first year Dara will have $903.125 in his account.
Step-by-step explanation:
Since this a compounded interest formula, it means that the amount invested grows exponentially overtime. In order to calculate the total of money over a period of time we must use the following formula:
M(t) = M(0)*(1 + r/n)^(n*t)
Where M(t) is the amount of money in "t" years, M(0) is the amount invested, r is the anual interest rate, n is the compound period over a year and t is the time elapsed in years.
In this problem the amount is compounded half-yearly, this means that for every year that passes the money is compounded twice, therefore n is equal to 2. Applying the data from the problem to the formula, we have:
M(1) = 800*(1 + 0.125/2)^(2*1)
M(1) = 800*(1.0625)^(2)
M(1) = 800*(1.0625)^(2) =903.125
By the end of the first year Dara will have $903.125 in his account.