Question

√(1+sinα)怎么化成√「（sin(α/2)+cos(α/2)）²」和|sin(α/2)+cos(α/2)

Answer 1

1=sin²(a/2)＋cos²(a/2)及sina=2sin(a/2)cos(a/2)

则：

1＋sina

=sin²(a/2)＋2sin(a/2)cos(a/2)＋cos²(a/2)

=[sin(a/2)＋cos(a/2)]²