Q. Знайди об'єм тіла, отриманого при обертанні навколо осїаабсцис фігури, обмеженої лініями:y=6x2,y=6x
Identify Bounds and Region: Identify the bounds of integration and the region to be rotated.The curves intersect where 6x2=6x. Solving for x, we get x2=x, so x(x−1)=0. Thus, x=0 or x=1. These are the bounds for our integral.
Set Up Integral: Set up the integral for the volume using the disk method.The volume V is given by the integral from 0 to 1 of π(outer radius2−inner radius2)dx. Here, the outer radius is y from y=6x and the inner radius is y from y=6x2.
Express Radii and Plug In: Express the radii in terms of x and plug into the volume formula.Outer radius = 6x, Inner radius = 6x2.V=π∫01[(6x)2−(6x2)2]dx=π∫01[36x2−36x4]dx.
Compute Integral: Compute the integral.V=π∫01[36x2−36x4]dx=π[12x3−7.2x5] from 0 to 1.Evaluating from 0 to 1, we get π[12(1)3−7.2(1)5]=π[12−7.2]=4.8π.