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Solve trigonometric function

cos2∅ + sin∅ × csc∅ / sin2∅

User Fadly Dzil
by
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1 Answer

4 votes

Answer:


\cot(\theta)

Explanation:

Trig identities:


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


sin^2(\theta)+cos^2(\theta)=1


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


\implies \cos(2\theta)=2cos^2(\theta)-1


\implies2cos^2(\theta)= \cos(2\theta)+1


\sin(2\theta)=2\sin(\theta)\cos(\theta)

Therefore,


(\cos(2\theta)+\sin(\theta) * \csc(\theta))/(\sin(2\theta))


=(\cos(2\theta)+(\sin(\theta))/(\sin(\theta)))/(\sin(2\theta))


=(\cos(2\theta)+1)/(\sin(2\theta))


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


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


=(cos(\theta))/(\sin(\theta))


=\cot(\theta)

User Jango
by
5.5k points