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Wholewheat458
Aug9-08, 12:15 AM
Here is my problem:
(sec 2 x csc x) / (sec 2 x + csc 2 x)
-first i replaced the denominator with its identities.. and i got : 2+tan^2 x +cos^2 x
but the numerator.. can you just .. i really think i'm doing this
wrong.. ugh, and i cannot stand it!!
Honestly, i would be truly gratful for any help ^^
:shy:

snipez90
Aug9-08, 12:20 AM
Um, is there an actual identity this expression is a part of? That's not really a problem, it's just an expression. Are you being asked to transform it into a nicer form? There are many, many possibilities for different expressions that are equivalent to the one you gave.

Wholewheat458
Aug9-08, 12:21 AM
^^ oh, i'm actually suposed to simplify the expression in the most complete form

snipez90
Aug9-08, 12:28 AM
Ok and to double check your original expression is [sec(2x)csc(x)] / [sec(2x) + csc(2x)] right?

Wholewheat458
Aug9-08, 12:31 AM
oh,.. no, i forgot the carrots sorry, the sec,sec, and csc are all squared
(sec^2 x csc x) / (sec^2 x + csc^2 x)

snipez90
Aug9-08, 12:36 AM
Ok, first, try writing everything in terms of sin and cos (often a good technique). The key lies in simplifying the denominator since you can't do much with the numerator after writing it in terms of sin and cos.

Here's a hint for the denominator. Since we're dealing with sums of reciprocals, use the fact that 1/a + 1/b = (a+b)/ab.

Wholewheat458
Aug9-08, 12:43 AM
^^ WOOT!! Hahahhaha!! the answer is sin x!!!!
thank you so much!!

snipez90
Aug9-08, 12:57 AM
No problem! Also, this is more trig and less calculus and you're likely to get more help in the precalculus section of the homework area anyways. That way you'll get your problem answered faster without confusing people :).