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HELP!!! ASAP!!!! TRIG!!!

HELP!!! ASAP!!!! TRIG!!!-example-1
User Favo
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1 Answer

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18 votes

Answer:

Identity is true

Explanation:


(cos\theta+1)/(tan^2\theta)=(cos\theta)/(sec\theta-1)


(cos\theta+1)(sec\theta-1)=(tan^2\theta)(cos\theta)


(cos\theta)(sec\theta)+(cos\theta)(-1)+(1)(sec\theta)+(1)(-1)=((sin^2\theta)/(cos^2\theta))(cos\theta)


(cos\theta)((1)/(cos\theta))-cos\theta+sec\theta-1=(sin^2\theta)/(cos\theta)


1-cos\theta+sec\theta-1=(sin^2\theta)/(cos\theta)


-cos\theta+sec\theta=(sin^2\theta)/(cos\theta)


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


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


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


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


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

Therefore, the identity is true.

Helpful tips:

Pythagorean Identity:
sin^2\theta+cos^2\theta=1\\cos^2\theta=1-sin^2\theta\\sin^2\theta=1-cos^2\theta

Quotient Identities:
tan\theta=(sin\theta)/(cos\theta),sec\theta=(1)/(cos\theta)

User Pablo Castellazzi
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