csc x / [ cot x + tanx ] = write in terms of sine and cosine
[ 1 / sin x] / [( cos x / sinx) + (sin x / cos x) ] get a common denominator on the bottom
[ 1 / sinx] / ( [ cos^2 x + sin^2 x ] / [sin x cosx ] ) =
1 [ cos^2 x + sin^2 x ]
___ ÷ ___________________ =
sin x sin x cosx
1 sin x cos x
___ X ___________________ = swap numerators
sin x [ cos^2 x + sin^2 x ]
sin x cos x X 1
_________ ____ =
sin x 1
cos x
