given an ellipse in vector form(adsbygoogle = window.adsbygoogle || []).push({});

r(phi)=a*cos(phi)i+b*sin(phi)j

whereiandjare the unit vectors for x and y,

then y= b*sin(phi), and x = a*cos(phi).

tan(phi) = y / x ,

but y/x=(b/a)*tan(phi)

which implies 1 = b/a or b=a

which is false.

What is the deal?

doing the same for a circle leads to the true statement, 1=1.

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# Simple ellipse question

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