(4)
Adding (3) and (4), we get, the required area = 4π Example 5 Find the area bounded by the ellipse 
2
2
2
2
1
x
y
a
b
+
=  and the ordinates x = 0
and x = ae, where, b2 = a2 (1 – e2) and e < 1 Solution The required area (Fig 8 12) of the region BOB′RFSB is enclosed by the
ellipse and the lines x = 0 and x = ae