2x^2-5x+3=02(x²-5x/2)+3=02(x-5/4)²+3-25/8=02(x-5/4)²=1/8(x-5/4)²=1/16x-5/4=±1/4x=1或x=3/2 十字相乘法2x^2-5x+3=0(2x-3)(x-1)=0x=1或x=3/2
x²-5/2x+3/2=0（x-5/4）²-25/16+3/2=0(x-5/4)²=1/16x-5/4=±1/4x=1,或3/2
