Question

求弓形面积现在只知道半径R=1.25,H=0.87,求面积

Answer 1

1.25 - 0.87 = 0.38

AD = √(1.25² - 0.38²) = 1.19

1.19 * 0.38 = 0.4522

COS(a/2) = 0.38/1.25 = 0.304 a/2 ≒ 72.3 a ≒ 144.6

1.25 * 1.25 * π * (144.6/360) - 0.4522 = 1.518