Current location - Training Enrollment Network - Mathematics courses - 3.( 1)(2) How to do it? Please use the sixth grade method to solve the homework problem in the next semester, that is to say, don't use it.
3.( 1)(2) How to do it? Please use the sixth grade method to solve the homework problem in the next semester, that is to say, don't use it.
(1) analysis: subtract the area of two 1/4 circles (that is, half a circle) from the rectangular area.
Solution: Rectangular area: 4*2=8 Circular area formula S=π r? = π 2 = 4π, the area of the semicircle is 2π, and the area of the shadow part is 8-2π.