用配方法解方程x²-2x-1=0时,配方后-搜答案-智慧作业帮

4分之1x²-2x-12=0x²-8x-48=0(x-4)²=64x-4=8或x-4=-8x=12,或x=-4

（2x--1）（x–1）=0x=1/2x=1

2x平方-4x-1=02x^2-4x+2=32(x-1)^2=3(x-1)^2=3/2x-1=±√6/2x=1+±√6/2

x²-1=√2x/2x²-√2x/2=1x²-√2x/2+1/8=9/8(x-√2/4)²=18/16x=√2/4+3√2/4x=√2/4-3√2/4x=√2x

解由2x²+4x+1=0得2x²+4x+2-1=0即2（x²+2x+1）-1=0即2（x+1）²-1=0即2（x+1）²=1

答：2x²-4x+1=02(x²-2x+1)-2+1=02(x-1)²=1(x-1)²=1/2x-1=±√2/2x=1±√2/2

3x^2-6x+1=03(x^2-2x)+1=03(x^2-2x+1)+1-3=03(x-1)^2=2(x-1)^2=2/3选D

x²+4x+2=0x²+4x+4=2(x+2)²=2∴x=-2+√2x=-2-√22、方法一：(1)+(2)得2a=4a=2把a=2代入(1)得√3b=1∴3b²

3(x^2+x/3-1/3)=0x^2+x/3-1/3=0x^2+2*(1/6)x+(1/36)-1/3-1/36=0(x+1/6)^2=13/36x1=(-1+√13)/6x2=-(1+√13)/6

3x^2+6x-1=0x^2+2x-1/3=0x^2+2x+1-1-1/3=0(x+1)^2-4/3=0(x+1-2√3/3)(x+1+2√3/3)=0x=-1+2√3/3或x=-1-2√3/3

x^2-2x=2x+1x^2-4x=1x^2-4x+4=1+4(x-2)^2=5x-2=±√5x=2±√5

(x+2)²+(x-1)²=4(x²+1)x²+4x+4+x²-2x+1=4x²+8x+42x²+6x=1x²+3x=1

(2x-1)^2-(4x-1)=34x²-4x+1-4x+1=34x²-8x=14(x²-2x+1)-4=14(x-1)²=5(x-1)²=5/4x-

(2x-1)(3x-1)=3-6x6x²-5x+1=3-6x6x²+x=2x²+1/6x=1/3x²+1/6x+1/144=1/3+1/144(x+1/12)&

2X^2-6X+1=0可以用配方法和公式法△=36-4x2=28x=(6+2倍根号7）/4x=(6-2倍根号7）/4X=（3+根号7）/2X=（3-根号7）/2希望能帮到你!

两边除以-2x²-x=1/2x²-x+1/4=1/2+1/4(x-1/2)²=3/4x-1/2=±√3/2x=(1-√3)/2,x=(1+√3)/2

2x(x-2)=12x^2-4x+1=02(x^2-2x+1)=12(x-1)^2=12(x-1)=1或2(x-1)=-1x=3/2或x=1/2

解方程：2(x-3)=x+3方程左边展开得到：2(x-6x+9)=x+3则2x-12x+18=x-3方程左右两边同时加上(3-x)得到：2x-13x+21=0则(2x-7)(x-3)=0解得x1=7/