Question
Two perpendicular tangents drawn to the ellipse
+ 
= 1 intersect on the curve -
- x = a/e
- x2 + y2 = 41
- x2 + y2 = 9
- x2 – y2 = 41
Hint:
find out the equation of director circle.
The correct answer is: x2 + y2 = 41
x2+y2= 41
We know that perpendicular tangents are drawn from the director circle. Hence, equation of director circle :
x2+y2= a2+b2
x2+y2= 25+16 = 41
x2+y2= 41
the tangents drawn from the director circle intersect at right angle.
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