母线长为1的圆锥体积最大时,其侧面积展开图圆心角为多少?答案是2√6/3π

问题描述:

母线长为1的圆锥体积最大时,其侧面积展开图圆心角为多少?答案是2√6/3π

假设圆锥的底面圆半径为x高为y则 有x*x+y*y=1(勾股定理)此时;x*x=1-y*y圆锥的体积为V=(1/3)*π*x*x*y =(1/3)*π*(1-y*y)*y =-(1/3)*π*y*y*y+(1/3)*π*...