Talk:Calculus/Surface area

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[edit] went above my head

well if one does want to take averages then one should logically take sum (y+dy/2).ds and sum it up however if ds varies massively over the range (like a cone with a huge slope for the edge) then the calculations are still massively off

however if one views it as a small cylinders of thickness ds and radius y , like a step of cylinders..it somehow seems to make sense. perhaps someone can help correct my understanding