Expert: Guido Feliz, Jr - 4/21/2004

Question
Problem 1.

Prove the follwoing identity:

tanX + cotX/sinXcosX = 1/cos^2Xsin^2X

(the tanX + cotX are over(or divided By) the SinXCosX and please note that the 1 over the cos^2Xsin^2X are squred.)

Problem 2.
Prove the follwoing identity:

sin(4X)= 4sin(X)cos(X)[cos^2(X)-sin^2(X)]

Please help me!!

Answer
Anita,

I just answered one of your trig questions.  I can only dedicate one question per student.  However, to solve trig identities, convert everything to sine and cosine and it will make identities much easier to tackle.  Always tackle the harder side of the equation first.  You can also go to "ask dr math" to find easy steps for solving trig identity problems.

Feliz

P.S. Remember: Convert everything to sine and cosine and it should be easy from there on.