2x²-7x+3=0x²-7/2x+3/2=0(x-7/4)²=49/16-3=1/16x-7/4=1/4或-1/4x=2或3/2
先乘出来,得2X^2-7x+3=o再配方得(X-3)(2X-1)=0OK
2X²-7X+3=0(2X-1)(X-3)=0X=1/2或X=3