Question

Determine the volume of the right circular cone generated by rotating the line y = 1/3x about the y-axis between y = 0 and y = 3.
A) V = 81pi cu.units
B) V = 84pi cu.units
C) V = 82pi cu.units
D) V = 85pi cu.units
E) V = 83pi cu.units @Calculus1

Answer 1

A.

Answer 2

do u want the working?

Answer 3

ok

Answer 4

Ok i'm assuming that it's y=x/3 not y = 1/(3x).

Rotating around the y-axis; solve for x.
y = x/3.
x = 3y.

Find x^2.
x^2 = 9y^2.

Integrating it using the limits of 0 and 3, remember to add the pi and integrate 9y^2.

It comes out to be:
81pi cubic units.

Answer 5

A is correct.

Answer 6

Thanks a lot