x属于[0,π/2],则(2x-π/3)属于[-π/3,2π/3],则sin(2x-π/3)属于[-√3/2,1].显然,b的值不会引起变化,故有两种情况：（1）sin(2x-π/3)=-√3/2时f(x)=-5;sin(2x-π/3)=1时,f(x)=1则-10a+b=-5;2a+b=1 得：a=0.5 b=0（...