Question

x = r cos theta , y = r sin theta .
eliminate theta

Answer 1

Cos theta=X/r Sin theta=Y/r

we know that, Cos^2theta+Sin^2theta=1

So that, (X/r)^2+ (Y/r)^2=1

(X^2/r^2)+(Y^2/r^2)=1

so in this way we can eliminate the theta

Answer 2

Answer:

same

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