y=√(x²-3x+2)(x≤1或x≥2)=√[(x-3/2)²-1/4]想象开口向上,对称轴为x=3/2的抛物线,知:(-∞,1）上递减(2,+∞)上递增也可以用求导:(x≤1或x≥2)y'=(2x-3)/2√(x²-3x+2)另y'=0,得x=3/2(舍)当x0则函数在(...