Given:
A circle of radius r inscribed in a square.
To find:
The expression for the area of the shaded region.
Solution:
Area of a circle is:
[tex]A_1=\pi r^2[/tex]
Where, r is the radius of the circle.
Area of a square is:
[tex]Area=a^2[/tex]
Where, a is the side of the square.
A circle of radius r inscribed in a square. So, diameter of the circle is equal to the side of the square.
[tex]a=2a[/tex]
So, the area of the square is:
[tex]A_2=(2r)^2[/tex]
[tex]A_2=4r^2[/tex]
Now, the area of the shaded region is the difference between the area of the square and the area of the circle.
[tex]A=A_2-A_1[/tex]
[tex]A=4r^2-\pi r^2[/tex]
[tex]A=4r^2-\pi r^2[/tex]
[tex]A=r^2(4-\pi )[/tex]
Therefore, the correct option is (a).
