若圆的半径为r,直径为d,圆周长为c,圆心角的度数为n,弧长为L,则弧长L=___=___=___.

问题描述:

若圆的半径为r,直径为d,圆周长为c,圆心角的度数为n,弧长为L,则弧长L=___=___=___.

L = nc/360 = 2πrn/360 = πdn/360