Question

show that cosx - cos^3 x over sinx is equal to sinxcosx

Answer 1

$=cosx/sinx - cos ^3x/sinx$ $=1/tanx-cos^2 x/tanx$

$=(1-cos^2x)/tanx$

$=sin^2x/tanx$

$=sin^2x/(sinx/cosx)$

$=sinxcosx$