解：2x²-7x+6=0x²-7x/2=-3x²-7x/2+(7/4)²=-3+49/16(x-7/4)²=1/16x-7/4=±√(1/16)x=7/4±1/4x1=2 x2=3/2
(x-2)(2x-3)=0x1=2x2=3/2
