How do you find the volume of the solid obtained by rotating the region bounded by the curves Y=2x and Y=x^2 rotated around the x-axis?

1 Answer
May 23, 2015

Remembering that the area between f(x) and g(x), with f(x) over g(x) from x_1 to x_2 is given by:

int_(x_1)^(x_2)[f(x)-g(x)]dx,

and since y=2x is over the function y=x^2, and the intercept point is given by the system:

y=2x

y=x^2

2x=x^2rArrx(x-2)=0rArr

x_1=0 and x_2=2,

then:

int_0^1(2x-x^2)dx=[x^2-x^3/3]_0^2=

=[2^2-2^3/3-(0^2-0^3/3)]=4-8/3=4/3.