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Area lying in the first quadrant and bounded by the circle x^{2} + y^{2} = 4 and the lines x = 0 and x = 2 is

The area bounded by the circle and the lines, x = 0 and x = 2, in the first quadrant is shown by shaded region in above figure.

Area of OAB =

Therefore, required area is = π square units.

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13

Area of the region bounded by the curve y^{2} = 4x, y-axis and the line y = 3 is