Question

已知α=（π,3π/2）化简√(1+sinα)-√(1-sinα)+√(2+2cosα)-√(2-2cosα)

Answer 1

π/2cos(a/2)

tan(a/2)-cos(a/2)

sin(a/2)+cos(a/2)>0

原式=sin(a/2)+cos(a/2)-(sin(a/2)-cos(a/2))-2cos(a/2)-2sin(a/2)

=2cos(a/2)-2cos(a/2)-2sin(a/2)

=-2sin(a/2)