设t=sin(2x+π\6),则t的范围为[-1\2,1],f(x)=-2at+2a+b 把t=-1\2和t=1分别代入f(x)中,得 f(x)=3a+b和f(x)=b (1)3a+b=-5,b=1,解,得a=-2,b=1 (2)b=-5,3a+b=1,解,得a=2,b=-5