Question

已知角a的终边与函数5x+12y=0(x小于等于0),则cosa+1/tana--1/sina的值为?

Answer 1

5X+12Y=0

y=-5/12x

tanα=k=-5/12

X小于等于0,∴α在第二象限

cosα=-1/根号(1+tan^2α)=-1/根号(1+5^2/12^2)=-12/13

sinα=根号(1-cos^2α)=根号(1-12^2/13^2)=5/13

cosα+1/tanα-1/sinα

=-12/13+1/(-5/12)-1/(5/13)

=-12/13-12/5-13/5

=-12/13-5

=-77/13