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Trig Functions question 
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#1
Apr907, 11:29 AM

P: 4

1. The problem statement, all variables and given/known data
Simplify: cosx / (1+sinx) 2. The attempt at a solution 1 / (sec x)(1+sin x) 1 / (sec x + (sin x / cos x)) 1 / (sec x + tan x) I know that the answer is sec x  tan x but don't know how to get there. Any help would be appreciated. 


#2
Apr907, 11:42 AM

P: 123

Do you know what the value of [tex]sec^2xtan^2x[/tex] is?
The difference of two squares helps too. 


#3
Apr907, 11:49 AM

P: 4

sec^2 (x)  tan^2 (x) = 1
but nothing's squared in the problem 


#4
Apr907, 11:53 AM

P: 123

Trig Functions question
Not until you do some multiplying.
Do you understand what I mean by the difference of two squares? 


#5
Apr907, 11:57 AM

Sci Advisor
HW Helper
Thanks
P: 25,251

You could also just multiply top and bottom of your given expression by (1sin(x)) and expand. It's really the same thing as jing is suggesting.



#6
Apr907, 12:01 PM

P: 4

OK, So it's
(sec x  tan x) / (sec x + tan x)(sec x tan x) = (sec x  tan x) / 1 = sec x tan x Thank you so much!! 


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