已知sin(x+π/3)=1/4,求sin(2π/3-x)+cos²(π/6-x)
问题描述:
已知sin(x+π/3)=1/4,求sin(2π/3-x)+cos²(π/6-x)
答
sin(2π/3-x)+cos²(π/6-x)
=sin(x+π/3)+sin²(π/3+x)
=1/4+1/16
=5/16
答
sin(2π/3-x)+cos²(π/6-x)=sin[π-(2π/3-x)]+sin²[π/2-(π/6-x)]
=sin(x+π/3)+sin²(x+3/π)
=1/4+(1/4)²
=5/16
有不明白的地方再问哟,祝你学习进步,更上一层楼! (*^__^*)