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Can somebody please help me? (PreCalc)

Can somebody please help me? (PreCalc)-example-1

1 Answer

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\csc\theta=\frac1{\sin\theta}=\frac{√(17)}}4\implies\sin\theta=\frac4{√(17)}

Recall that
\sin^2\theta+\cos^2\theta=1, which means


\cos\theta=\pm√(1-\sin^2\theta)=\pm\sqrt{1-(16)/(17)}=\pm\frac1{√(17)}

Since
\tan\theta=(\sin\theta)/(\cos\theta)>0, and
\sin\theta>0, it follows that
\cos\theta>0 too, so you take the positive root:


\cos\theta=\frac1{√(17)}

Therefore


\cot\theta=(\cos\theta)/(\sin\theta)=\frac{\frac1{√(17)}}{\frac4{√(17)}}=\frac14
User Srokatonie
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