Current location - Training Enrollment Network - Mathematics courses - The area of the color part of the math problem in the second volume of the sixth grade:
The area of the color part of the math problem in the second volume of the sixth grade:
Ideas:

Shadow 1: rectangular area-area of the left half of the semicircle =6×3-π×3×3÷4

Shadow 2: the area of the right half of the semicircle-right angle△ △CDB area =π×3×3÷4-3×3÷2.

Shadow area = shadow one+shadow two = 18-4.5= 13.5.