Ellipse: 4 Practice questions based on chord of an ellipse (details in description)

Ellipse: 4 Practice questions based on chord of an ellipse Q1: PQ is a variable chord of ellipse x^2/a^2+y^2/b^2=1. If PQ subtends right angle at the center O, then 1/OP^2+1/OQ^2= Q2: The condition on a and b such that the two chords of ellipse x^2/2a^2+y^2/2b^2=1 passing through (a,-b) are bisected by x+y=b Q3: If the line lx+my=n cuts the ellipse in points whose eccentric angle differs by pi/2, then (a^2l^2+b^2m^2)/n^2 = Q4: If the chord joining two points having eccentric angle a and b, cut the major axis of ellipse at a distance c units, then tana/2tanb/2 = Twitter handle:   / mathsmerizing   Support the channel: UPI link: 7906459421@okbizaxis UPI Scan code: https://mathsmerizing.com/wp-content/... PayPal link: paypal.me/mathsmerizing