Simone谁能帮我推导出圆锥侧面积公式为什么是S=πRL
的有关信息介绍如下：解：圆锥的侧面展开是一个扇形，如下图扇形ABC，则圆锥的侧面积=扇形的面积。
设：圆锥底面的半径OB长为R，圆锥的母线也即扇形的半径AB长为L，
则 扇形的弧长B⌒C=底面的圆周长2πR， 扇形的面积=1/2x弧长x半径=1/2(2πR)L=πRL,
也即 圆锥的侧面积=πRL。
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解：圆锥的侧面展开是一个扇形，如下图扇形ABC，则圆锥的侧面积=扇形的面积。
设：圆锥底面的半径OB长为R，圆锥的母线也即扇形的半径AB长为L，
则 扇形的弧长B⌒C=底面的圆周长2πR， 扇形的面积=1/2x弧长x半径=1/2(2πR)L=πRL,
也即 圆锥的侧面积=πRL。
