find the area of the region : {(x,y) : x2 + y<=2ax, y2 >=ax, x,y >= 0}

the given regions are
x2+y22ax (x-a)2+y2a2  ...........(1)which is the region inside the circle with radius a and centre as (a,0)y2ax which is the region outside the parabola y2=ax .....(2)x,y0 i.e. region lies in the 1st quadrant .....(3)

therefore the required region is 
R=0a[2ax-x2-ax ].dx=0a2ax-x2.dx-a.0ax.dx=0aa2-(x-a)2.dx-a0ax1/2.dx=(x-a)a2-(x-a)22+a22.sin-1x-a20a-a.x3/23/20a        [since a2-x2.dx=xa2-x22+a22.sin-1xaR=(a-a)a2-(a-a)22+a22.sin-1a-a2-(0-a)a2-(0-a)22-a22.sin-10-a2                           -a.23.a3/2
R=0+0-0+a22.sin-11-23a2=a22.π2-23.a2=a2.(π4-23) sq units

hope this helps you

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