Prove the trig identity cos(2x)+sin^2(x)=1/2 sin(2x)cot(x)

Prove the trig identity cos(2x)+sin^2(x)=1/2 sin(2x)cot(x)

Postby Guest » Mon Apr 17, 2017 7:40 pm

Prove the trigonometric identity:
cos(2x)+sin^2(x)=1/2 sin(2x)cot(x)





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Re: Prove the trig identity cos(2x)+sin^2(x)=1/2 sin(2x)cot(

Postby Math Tutor » Wed Apr 19, 2017 1:18 am

[tex]cos(2x) = cos^2(x) - sin^2(x)[/tex]
[tex]sin(2x) = 2sin(x)cos(x)[/tex]

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[tex]cos(2x) + sin^2x = cos^2(x) - sin^2(x) + sin^2(x) = cos^2(x)[/tex]

[tex]\frac12 sin(2x)cot(x) = \frac{1}{2} 2sin(x)cos(x)\frac{cos(x)}{sin(x)} = cos^2(x)[/tex]

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Re: Prove the trig identity cos(2x)+sin^2(x)=1/2 sin(2x)cot(

Postby Math Tutor » Wed Apr 19, 2017 1:19 am

Is it clear?

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