Class 11

Math

Co-ordinate Geometry

Conic Sections

A tangent is drawn to the ellipse to cut the ellipse $a_{2}x_{2} +b_{2}y_{2} =1$ and to cut the ellipse $c_{2}x_{2} +d_{2}y_{2} =1$ at the points P and Q. If the tangents are at right angles, then the value of $(c_{2}a_{2} )+(d_{2}b_{2} )$ is