Trigonometric Identity Homework: Solving with Sin and Cos Formulas

AI Thread Summary
The discussion revolves around solving a trigonometric identity problem using sine and cosine formulas. The original poster is struggling with problem fifty and has attempted to convert everything to sine and cosine without success. A user points out an error in combining fractions, specifically regarding a lost minus sign during multiplication. The correct expression to use is provided as 4 tan(theta) / (1 - tan^2(theta)). The conversation highlights the importance of careful manipulation of terms in trigonometric identities.
Feodalherren
Messages
604
Reaction score
6

Homework Statement


Homework Equations



Any trig formulas

The Attempt at a Solution


one_0001.jpg

one_0002.jpg


The yellow paper is me switching everything to sin and cos to see if that helps but it doesn't. I'm completely stuck here.
 
Physics news on Phys.org
Oh yeah, it's problem fifty. Forgot to say that :).
 
Feodalherren said:
Oh yeah, it's problem fifty. Forgot to say that :).

What yellow paper ?
 
You can't see the images?
 
Feodalherren said:
You can't see the images?
Not at all.
 
http://img839.imageshack.us/img839/2928/one0001.jpg

Does that work?
 
Last edited by a moderator:
at the step where you combine the two fractions you sucked in the minus sign and then lost a minus as you multiplied the second term with 1-tan(theta). Do you see that?

you should instead have: 4 tan(theta) / ( 1 - tan^2(theta) )
 
Got it. Thank you!
 
Back
Top