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I’m so lost on this question i don’t even know where to start

I’m so lost on this question i don’t even know where to start-example-1
User Daniel W
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1 Answer

18 votes
18 votes

The given expression is:


\csc b(\csc b+\cot b)

It is required to simplify the expression to a single trigonometry function.

To do this, trigonometric identities have to be applied to simplify the expression.

The following trigonometry identities will be used:


\begin{gathered} \csc b=(1)/(\sin b) \\ \cot b=(\cos b)/(\sin b) \\ \sin^2b=1-\cos^2b \end{gathered}

Use the inverse trigonometry identities to rewrite the expression as:


\begin{gathered} (1)/(\sin b)((1)/(\sin b)+(\cos b)/(\sin b)) \\ Simplify\text{ the sum in parentheses:} \\ =(1)/(\sin b)((1+\cos b)/(\sin b)) \end{gathered}

Multiply the expressions:


(1+\cos b)/(\sin^2b)

Rewrite the denominator using the trigonometric identity:


(1+\cos b)/(1-\cos^2b)

Rewrite the denominator further using the difference of two squares of binomials:


(1+\cos b)/((1+\cos b)(1-\cos b))

Cancel out like terms in the numerator and denominator, so the expression becomes:


(1)/(1-\cos b)

Hence, the required answer.

User Huge
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