Circumference 4. Find the area of a square inscribed in this circle.

The diagonal of a square is equal to the product of its side a and the square root (notation √) of 2, that is, d1 = a × √ (2), we supply the value d1, we get a = 2 ÷ √ (2). The area of the square is S = a ^ 2, we get S = 4 ÷ 2 = 2.
Answer: 2

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