Let mid-point of part PQ which is in between the axis is R (x1,y1) , then coordinates of P and Q will be (2x1,0) and (0,2y1) respectively. ∴ Equation oflinePQis
x
2x1
++
y
2y1
= 1 ⇒ y = - (
y1
x1
) x + 2y1 If this line touches the ellipse
x2
a2
+
y2
b2
= 1 then it will satisfy the condition, x2 = a2m2+b2 So, (2y1)2 = a2(