Each cross section would be a square with side length equal to the vertical distance between the upper and lower semicircles defined by y(x), which is

√(9 - x ^2) - (- √(9 - x ^2)) = 2 √(9 - x ^2)

The area of each square section is the square of this length,

(2 √(9 - x ^2)) = 4 (9 - x ^2) = 36 - 4x ^2

We get the whole solid for -3 ≤ x ≤ 3, so integrating gives a volume of

$\displaystyle\int_{-3}^3(36-4x^2)\,\mathrm dx=\boxed{144}$

3 0

3 years ago

I need help on these three PLEASE!!

Sedaia [141]

idek it looks difficult

3 0

3 years ago

Read 2 more answers

Malorie can work 10 math problems in 3 minutes. At this rate, how many problems can she work in one hour?

lisov135 [29]

D
If you multiply 3 by 10 and add a zero onto the ten in the question that is 100 in half an hour, all you need to do then is multiply that answer by two to get your answer.

4 0

3 years ago