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Which of the following identities can you use to help vou show that tan (3x)=sin(6x)/1+cos(6x)Select all that apply 3 answers

Which of the following identities can you use to help vou show that tan (3x)=sin(6x-example-1
User Ajesamann
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1 Answer

13 votes
13 votes

Given


\tan3x=(\sin6x)/(1+\cos6x)

Find

Find which identities used to show


\tan3x=(\sin6x)/(1+\cos6x)

Step-by-step explanation

as,, we use


\begin{gathered} \sin2x=2\sin x\cos x \\ \cos2x=2\cos^2x-1 \end{gathered}

so ,


\begin{gathered} \sin(6x)=2\sin(3x)\cos(3x) \\ \cos(6x)=2\cos^2(3x)-1 \end{gathered}

now, substitute the values on the left side


\begin{gathered} (2\sin(3x)\cos(3x))/(1+(2\cos^2(3x)-1)) \\ \\ \frac{\begin{equation*}2\sin(3x)\cos(3x)\end{equation*}}{1+2\cos^2(3x)-1} \\ \\ (2\sin(3x)\cos(3x))/(2\cos^2(3x)) \\ \\ (\sin(3x))/(\cos(3x)) \\ \\ \tan(3x) \end{gathered}

Final Answer

Therefore . we use 3 identities which are A , B and D

User Inikulin
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