In order to promote a new product, a merchant solicited advertising terms and trademark patterns from the whole society. As a result, the trademark pattern as shown in the picture won the bid. Find the shaded area.

Problem-solving idea: The area of ??this shadow can be regarded as the area of ??a rectangle plus the area of ??a quarter circle, minus the area of ??a triangle.

Therefore, follow the steps to solve the problem as follows:

The area of ??the rectangle plus the area of ??a quarter circle = 1/4πa^2+2a^2,,

< p>The area of ??the triangle in the blank part=1/2×(2a+a)×a=3/2×a^2,

Then, the area of ??the shaded part=(1/4πa^2+2a^ 2)-3/2a^2=(π+2)/4×a^2.