Proving Trigonometric Identities

snowpanda
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Homework Statement



Prove (using the left side):

sinΘ tanΘ = cosΘ sec^2Θ - cosΘ

Homework Equations





The Attempt at a Solution

 
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sin(\theta)tan(\theta)= \frac{sin(\theta)}{cos(\theta)}tan(\theta)cos(\theta)= \tan^2(\theta)cos(\theta)

Now use the fact that tan^2(\theta)= sec^2(\theta)- 1.
 
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