(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Prove that the straight line x cos @ + y sin @ = p is a tangent to the ellipse x^{2}/a^{2}+ y^{2}/b^{2}if a^{2}cos^{2}@ + b^{2}sin^{2}@ =p^{2}.

u and v are the perpendicular distances of a tangent from the two points M(0,ae) and N(0,-ae) respectively. Prove that u^{2}+ v^{2 }is a constant.

2. The attempt at a solution

So far I have: xx_{1}/a^{2}+yy_{1}/b^{2}-1 = x cos@ + y sin@ - p

I don't know where to go from here and I know in the second part I have to use the perpendicular distance formula but I'm not sure what to sub in and why.

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# Homework Help: Ellipse perpendicular distance

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