Proving the Identity: sinA/(1+cosA)=tan(A/2)

Thread starter brandon26
Start date Oct 12, 2005
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Identity

AI Thread Summary

The discussion centers on proving the trigonometric identity sinA / (1+cosA) = tan(A/2). Participants express confusion about using the double angle formula for cos2ø to solve the problem. One user indicates they are struggling to apply the formulas correctly. Ultimately, the original poster states that the problem has been resolved and no further replies are needed. The conversation highlights the challenges some users face when working with trigonometric identities.

Oct 12, 2005

brandon26

Prove the identity:

sinA / (1+cosA) = tan (A/2).

Im going no where with this, please help?

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Oct 12, 2005

Fermat

Homework Helper

use the double angle formula for cos2ø.

Oct 12, 2005

brandon26

Sorry I don't understand. And I am trying to apply the double angle formulae but I am just getting confused.

Oct 12, 2005

brandon26

Problem solved...No need to reply

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