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I need help in math can you please help me

I need help in math can you please help me-example-1
User Gchbib
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1 Answer

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We are given the following trigonometric expression:


(\sin \theta-\csc \theta)/(\cos \theta)

We are asked to put this expression as a function of sines and cosines, t do this, let's remember the following relationship:


\csc \theta=(1)/(\sin \theta)

Now we replace this in the expression:


(\sin \theta-(1)/(\sin\theta))/(\cos \theta)

Now we do the operation in the numerator, like this:


(((\sin\theta)(\sin\theta)-1)/(\sin\theta))/(\cos \theta)

We simplify the result:


(\sin ^2\theta-1)/(\sin \theta\cos \theta)

now we use the following relationship:


\begin{gathered} \sin ^2\theta+\cos ^2\theta=1 \\ \cos ^2\theta=1-\sin ^2\theta \\ -\cos ^2\theta=\sin ^2\theta-1 \end{gathered}

replacing this in the expression


(-\cos ^2\theta)/(\sin \theta\cos \theta)

simplifying:


-(\cos \theta)/(\sin \theta)

Since we are asked to put the expression as a function of sines and cosines we can't simplify any further, therefore the previous expression is the result.

User Wemu
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