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A is the center of the circle, and the length of AB
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05 Jun 2026, 06:38
Explanation
Let \(r\) is the radius of the circle
then \(2r\) is the diameter of the circle or a side of the square.
Point A is the center of the circle, and B is the bottom-right corner of the square.
Using coordinates, place the square with corners (0, 0), (2r, 0), (2r, 2r), (0, 2r). Then
A=(r, r), B=(2r, 0).
Therefore,
\(AB=\sqrt{(2r−r)^2+(0−r)^2}=\sqrt{r^2+r^2}=r\sqrt{2}\)
\(AB=4\sqrt{2}\),
so
\(r\sqrt{2}=4\sqrt{2} ⇒r=4.\)
Thus the square's side length is
\(s=2r=8,\) and its area is \(s^2=8^2=64.\)
The circle's area is
\(πr^2=π(4^2)=16π.\)
The area of the shaded region is:
\(64-16π = 13.76\)
Only E equals 13.76
Answer: E