化简(sin2α+2sin^2α)/(1-tanα)

题目

化简(sin2α+2sin^2α)/(1-tanα)

答案

(2(sinα)^2+sin2α)/(1+tanα)=sin2α(2(sinα)^2/(2sinαcosα)+1)/(1+tanα)=sin2α*(tanα+1)/(1+tanα)=sin2α