已知sinα=-3/5,且α是第四象限角,则tan[cos(3π-α)-sin(5π+α)]=

问题描述:

已知sinα=-3/5,且α是第四象限角,则tan[cos(3π-α)-sin(5π+α)]=

cos(3π-α)=-cosa =-4/5 ,sin(5π+α)=-sina=3/5
tan[cos(3π-α)-sin(5π+α)]=tan(-7/5)