Question

If $x=\sqrt{a}sin\alpha$ and $y=\sqrt{a}cos\alpha$. Find the value of $y^2$ + $x^2$.

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Answer 1

x = $\sqrt{a}sin\alpha$ and y = $\sqrt{a}cos\alpha$

$x^2$ = $\sqrt{a}si{n}^2\alpha$ and $y^2$ = $\sqrt{a}co{s}^2\alpha$ $\Rightarrow$ $y^2$ + $x^2$ = $a(co{s}^2\alpha +si{n}^2\alpha )=a$