Volumes of Revolution Question help please! :(

This does look confusing, but draw a diagram. If the height of the cone is h, the upper limit is h. The other limit is 0 because the line passes through the origin and that will become the vertex of the cone.

So square the equation of the line, integrate between the limits of h and 0 and then multiply by pi.

not sure how I would integrate [(r/h)x]^2 ? the h squared denominator just makes me think you'd need a fancier method of integration than if there wasn't a fraction?

not sure how I would integrate [(r/h)x]^2 ? the h squared denominator just makes me think you'd need a fancier method of integration than if there wasn't a fraction?

Is there something wrong in this question? If the equation of the second line is x=r then surely the height of the generated cone would be r?

This does look confusing, but draw a diagram. If the height of the cone is h, the upper limit is h. The other limit is 0 because the line passes through the origin and that will become the vertex of the cone.

So square the equation of the line, integrate between the limits of h and 0 and then multiply by pi.

why isn't the upper limit r? because q says 'bounded by... the line x=r and the x-axis' ? I know that if I use h as the upper limit I get the right answer, bur I just don't get how I'd know to use it. thought the limits were on the x-axis, and isn't h, height, concerned with the y axis?

thanks