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luffy
Apr 10, 2007, 08:11 PM
1/sinxcosx-cosx/sinx=tanx

galactus
Apr 11, 2007, 06:53 AM
\frac{1}{sin(x)cos(x)}-\frac{cos(x)}{sin(x)}=tan(x)

Cross multiply left side:

\frac{sin(x)-sin(x)cos^{2}(x)}{sin^{2}(x)cos(x)}

Factor out sinx:

\frac{\sout{sin(x)}(\overbrace{1-cos^{2}(x)}^{\text{sin^2(x)}})}{\sout{sin(x)}(sin( x)cos(x)}

\frac{sin^{2}(x)}{sin(x)cos(x)}=\frac{sin(x)}{cos( x)}=tan(x)