化简 sin2α(1+tanαtanα/2)
问题描述:
化简 sin2α(1+tanαtanα/2)
答
sin2α(1+tanαtanα/2)
=2sinαcosα{〔1+(sinα/cosα)〔(1-cosα)/sinα〕}
=2sinαcosα+〔1+(1-cosα)/cosα〕
=2sinαcosα+2sinα(1-cosα)
=2sinαcosα+2sinα-2sinαcosα
=2sinα