对于包含于圆内或者与圆有关的阴影部分的面积问题,你能轻松求解吗?看看下面的问题吧。一、圆内的阴影部分面积计算例1如图1所示,AB是半圆的直径,AB=2r,C、D为半圆的三等分点,求阴影部分的面积。解析:连结OC、OD、CD,∵C、D是半圆弧的三等分点,∴∠AOC=∠COD=∠DOB=60°,∵OC=OD,∴∠ODC=∠DOB=60°, Can you easily solve the problem of the area that is contained in the circle or in the shadow of the circle? Look at the following question. First, the shadow of the circle part of the area calculation example 1 As shown in Figure 1, AB is the diameter of a semicircle, AB = 2r, C, D for the semicircle of the third point, and find the shadow area. Analysis: link OC, OD, CD, ∵C, D is a semicircular arc of the third point, ∴∠ AOC = ∠COD = ∠DOB = 60 °, ∵OC = OD, ∴∠ODC = ∠DOB = 60 ° ,