Question

函数y=sin^2*x-3sinx+2的最小值为

Answer 1

y=sin^2x-3sinx+2

=sin^2x-3sinx+9/4-9/4+2

=(sinx-3/2)^2-1/4

当sinx=1时,y的值最小

=(1-3/2)^2-1/4

=1/4-1/4

=0