SOLUTION: I need help solving this problem. {{{ sin(x)*tan(x)=(1-cos^2(x))/cos(x) }}} please help me i have been working on this four hours.

Algebra ->  Trigonometry-basics -> SOLUTION: I need help solving this problem. {{{ sin(x)*tan(x)=(1-cos^2(x))/cos(x) }}} please help me i have been working on this four hours.       Log On


   

Question 444008: I need help solving this problem. ++sin%28x%29%2Atan%28x%29=%281-cos%5E2%28x%29%29%2Fcos%28x%29++
please help me i have been working on this four hours.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
sin(x)*tan(x)=(1-cos^2(x))/cos(x)
..
For (0 <= x <= 90º)
sinxtanx=(1-cosx)/cosx
sinx(sinx/cosx)=(1-cosx)/cosx
cancel out cosx
sin^2x=1-cosx
1-cos^2x=1-cosx
cos^2x-cosx=0
cosx(cosx-1)=0
cosx=0
x=90º
cosx-1=0
cosx=1
x=0