Physics, Chemistry, Mathematics Forums

Represent the surface area, volume using similar terms and also using the semi-vertical angle.

Differentiate to get the required value. The question is very simple and can be easily. Give it a try again, you will surely be able to solve it.

^{problem from maxima and minima}

^{differentiate} v=1/3 pi r²h taking h= l² - r²

^dv/dr=0

^{therefore l=3r;therefore sine of semivertical angle = r/l}

^=r/3r

^=1/3