论文部分内容阅读
有这样一道求阴影部分面积的题,如下图(单位:厘采)。学生的解题思路是:两个小半圆的面积加上直角三角形的面积,再减去大半圆的面积。列式为: 3.14×(6/2)~2÷2+3.14×(8/2)~2÷2+6×8÷2-3.14×(10/2)~2÷2
There is such a problem with the shadow area, as shown below (unit: PCT mining). Student problem-solving ideas: the area of two small semicircles plus the area of a right-angled triangle, minus the area of the big semicircle. The formula is: 3.14 × (6/2) ~ 2 ÷ 2 + 3.14 × (8/2) ~ 2 ÷ 2 + 6 × 8 ÷ 2-3.14 × (10/2) ~ 2 ÷ 2