SOLUTION: Can you prove the following identity algebraically. Sec x — cos x = sin x tan x

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Question 1152016: Can you prove the following identity algebraically.
Sec x — cos x = sin x tan x
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
sec (x) - cos( x) = sin( x) tan( x)

manipulate left side:
sec+%28x%29+-+cos%28+x%29 ...................use identity sec+%28x%29+=1%2Fcos%28x%29
=1%2Fcos%28x%29+-+cos%28+x%29......common denominator is cos%28x%29
=1%2Fcos%28x%29+-+cos%5E2%28+x%29%2Fcos%28x%29
=%281+-+cos%5E2%28+x%29%29%2Fcos%28x%29.......use identity sin%5E2%28x%29%2Bcos%5E2%28x%29=1=>1+-+cos%5E2%28+x%29=sin%5E2%28x%29
=sin%5E2%28+x%29%2Fcos%28x%29......write sin%5E2%28+x%29 as sin%28+x%29%2Asin%28+x%29
=%28+sin%28+x%29%2Ahighlight%28sin%28+x%29%29%29%2Fhighlight%28cos%28x%29%29.......use identity sin%28x%29%2Fcos%28x%29=tan%28x%29
=+sin%28+x%29%2Atan%28+x%29