Can I calculate the volume of any function rotated once about the y-axis by multiplying the definite integral of that function by 2*pi*r?(adsbygoogle = window.adsbygoogle || []).push({});

For example if we want to generate a solid 3d shape from the function -x^2+1 we multiply the integral of it, (x - x^3 / 3), by 2*pi*1. The reason r is one in this case is because the points where the function crosses the x axis are 1 unit away from the y axis: (-1,0) and (1,0.)

(I have not taken a calculus class yet, this is just my personal reasoning.)

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# Tackling the Volume Integral

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