# Thread: Need some help and explanation...

1. ## Need some help and explanation...

ok, i gotta solve these equations and my answers have to be $0\leq x \leq 360^o$

$2sin^2x-3cosx=0$

and

$2cosx+3tanx=0$

I don't know how to solve these equations...

2. Originally Posted by crosser43
ok, i gotta solve these equations and my answers have to be $0\leq x \leq 360^o$

$2sin^2x-3cosx=0$

change $\textcolor{red}{sin^2{x}}$ to $\textcolor{red}{1 - cos^2{x}}$ and solve the resulting quadratic

and

$2cosx+3tanx=0$

multiply every term by $\textcolor{red}{\cos{x}}$ , then change $\textcolor{red}{\cos^2{x}}$ to $\textcolor{red}{1 - \sin^2{x}}$ ... same drill, solve the resulting quadratic.
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