(2cosalf-sinalf)/(2sinalf+cosalf), если ctgalf=-0,5

Question

(2cosalf-sinalf)/(2sinalf+cosalf), если ctgalf=-0,5

Answer 1

cosa/sina=-0.5   cosa=-0.5sina

(2*0.5sina-sinalf)/(2sinalf-0.5sina)=(-2sina)/(1.5sina)=-20/15=-4/3