弓形面积公式 弦长28.62m,3m,求弓形面积?
问题描述:
弓形面积公式 弦长28.62m,3m,求弓形面积?
答
28.62^2*3.14-(28.62^2-(28.62/2)^2)
=819.1044*3.14-(819.1044-204.7761)
=2571.987816-614.3283
=1957.659516
答
弓形所在圆的半径R:R²=(R-2.3)²+(28.62/2)²R²=R²-4.6R+2.3²+14.31²R=(2.3²+14.31²)/4.6=45.667圆心角2α,tanα=(28.62/2)/(R-2.3)=(28.62/2)/(45.667-2.3)=0.33,2α=2...