(1).f(x)=ab=m(1+sin2x)+cos2x
=msin2x+cos2x+m
∵函数过点(π/4,2)
∴msin(2×π/4)+cos(2×π/4)+m=2
m+m=2
m=1
(2).y=f(x)=sin2x+cos2x+1=√2sin(2x+45°)+1
当f(x)取最小值时
即sin(2x+45°)=-1
∴2x+π/4=2kπ-π/2
∴x=kπ-3π/8