A square is inscribed in a circle of radius 1 unit, and a larger square is circumscribed about the same circle. What is the area of the region located between the two squares?

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2 Answers
Jan 11, 2018

A=2 " unit"^2A=2 unit2

Explanation:

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Area of a square is given by : A=1/2d^2A=12d2, where dd is the length of the diagonal of the square.
Given radius of the circle r=1r=1,
=> OA=1OA=1,
=> "diagonal of the smaller square"=AB=2*OA=2diagonal of the smaller square=AB=2OA=2,
=> "area of the smaller square " A_S=1/2*AB^2=1/2*2^2=2area of the smaller square AS=12AB2=1222=2
=> OE="radius"=1, => ED=1OE=radius=1,ED=1,
=> CD=2ED=2CD=2ED=2
=> "area of the larger square " A_L= CD^2=2^2=4area of the larger square AL=CD2=22=4
Hence, area of the region located between the two squares == shaded area = A_L-A_S=4-2=2 " unit"^2=ALAS=42=2 unit2

Jan 11, 2018

Difference in areas of the two squares = 2 sq. units

Explanation:

radius of circle r = 1r=1

Diagonal of inner square d_s = 2r = 2ds=2r=2

Area of inner square A_s = (1/2) (d_s)^2 = (1/2) * 2^2 = 2As=(12)(ds)2=(12)22=2

Side of outer square a_S = 2r = 2aS=2r=2

Area of outer square A_S = a^2 = 2^2 = 4AS=a2=22=4

Difference in areas = 4 - 2 = 2 sq. units