Question

向量m=(1,sin(wx+60度)),n=(2,2sin(wx-30度)),若w=1,x属于[30度,120度],求m

Answer 1

m=(1,sin(wx+60度)),n=(2,2sin(wx-30度)),m平行n时,2sin(wx-30度)=2sin(wx+60度),sin(x-30°)=sin(x+60°)(√3/2)sinx-(1/2)cosx=(1/2)sinx+(√3/2)cosx(√3-1)sinx=(√3+1)cosxtanx=(√3+1)/(√3-1)=2+√3...