①(2cosα+3sinα)/(3cosα+sinα) (2+3tanα)/(3+tanα)2(si

①(2cosα+3sinα)/(3cosα+sinα) (2+3tanα)/(3+tanα)2(si

(2cosα+3sinα)/(3cosα+sinα) 分子分母同时除以cosa就可得到答案2(sinα)^2+sinαcosα-3(cosα)^2因为sinαcosα＝1/2 sin2a2(sinα)^2= - (1－2(sina)^2)+1= - cos2a+1-3(cosα)^2=-3/2(2(cosα)^2-1)-3/2=-3/2 cos2a-3/2所以原式＝1/2 sin 2a-5/2 cos 2a-1/2=√26／2sin(2a-b) (tanb=5）tanα√((1/((sinα)^2))-1)根号内：通分得(1-(sina)^2)/(sina)^2,因为1＝(sina)^2＋(cosa)^2所以得(cosa)^2/(sina)^2带上根号得[cota]所以原式＝1或－1======以下答案可供参考======供参考答案1:(1)(2cosα+3sinα)/(3cosα+sinα)=(2cosα/cosα+3sinα/cosα)/(3cosα/cosα+sinα/cosα)=(2+3tanα)/(3+tanα)2(sinα)^2+sinαcosα-3(cosα)^2=(2sinα+3cosα)(sinα-cosα)(2)tanα√((1/((sinα)^2))-1)=tanα√[(1-(sinα)^2)/(sinα)^2]=tanα√[(cosα)^2/(sinα)^2]=tanα*|cotα|=1或-1供参考答案2:①(2cosα+3sinα)/(3cosα+sinα)分子分母同除以cosα，结果就是答案了。2(sinα)^2+sinαcosα-3(cosα)^2=1/2sin2α+2-5(cosα)^2∵2(cosα)^2-1=cos2α∴1/2sin2α+2-5(cosα)^2=1/2sin2α-5/2cos2α-1/2=1/2（sin2α-5cos2α-1）②tanα√((1/((sinα)^2))-1)

这个答案应该是对的