sin(a+60)-sina=3/5,-90

sin(a+60)-sina=3/5,-90 已知sin=-3/5,那么(cosa+sina/cosa-sina)+(cosa-sina/cosa+sina)(a代表角, sin(a-pia/4)=3/5,求sina 已知3SIN^2A+2SIN^2B=5SINA,求SIN^2A+SIN^2B范围 若(sina+cosa)/(sina-cosa)=2,则sin(a-5派)*sin(3派/2-a)等于? 若(sina+cosa)/(sina-cosa)=2,则sin(a-5pai)*sin(3pai/2-a)等于? 已知sina+3cosa/3cosa -sina =5,则sin平方a-sina*cosa的值是? 证明：[sin(a-60)]^2+[sina]^2+[sin(a+60)]^2=3/2 已知sin(a+kpai)=-2cos(a+kpai)(k属于z)求(4sina-2sina)/(5sina=3sina)1.(4sina-2sina)/(5sina=3sina)2.0.25sin^2 a+0.4cos^2 a在线等,需要过程,有答案了会加分求(4sina-2cosa)/(5cosa+3sina) 之前打错 已知sin(a+60)+sina=-(4根3)/5,-90 已知sin(a+60°)+sina=-4√3/5,-90° 已知(sina+cosa)/(sina-cosa)=3 则2sin'a+(sina-cosa)'=? sin(2π+a) ,sin(π+a),sin(5π+a) 的区别为什么sin(2π+a) =sina sin(π+a)=-sina sin(a-p)cosa-cos(p-a)sina=3/5sin(a-p)cosa+cos(a-p))sina=3/5 5sin(A B) 3sinA,求tan(A B/2)*cotB/25sin(A+B)+3sinA=0,求tan(A+B/2)*cotB/2 若sina+cosa/sina-cosa=2,则4sin^2a-3sinacosa-5cos^2a= sin(a+kpai)=-2cos(a+kpai),k属于Z求(4sina-2cosa)/(5cosa+3sina) sin(a+kπ)=2cos[a+(k+1)π].求5cosa+3sina/4sina-2cosa