已知sin(x+π/6)=0.25,则sin(5π/6-x)+sin(π/3-x)*sin(π/3-x)的值为多少
问题描述:
已知sin(x+π/6)=0.25,则sin(5π/6-x)+sin(π/3-x)*sin(π/3-x)的值为多少
答
由sin(x+π/6)=0.25得cos(x-π/3)=-0.25,原试可整理为
cos(x-π/3)+1-cos(x-π/3)*cos(x-π/3)=11/16