x的平方减x等于1配方法-搜答案-百度作业网

4x²-4x+1=0(2x-1)²=0x=1/2

3x^2+6x-5=03(x^2+2x+1)=8(x+1)^2=8/3x1=√(8/3)-1x2=-√(8/3)-1

x^2+4X-3=0x^2+4x=3x^2+4x+(4/2)^2=3+(4/2)^2(x+2)^2=3+4=7x+2=±√7x=－2±√7x1=-2+√7x2=-2-√7

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

x的平方加3x减4等于0x^2+3x+9/4-4-9/4=0(x+3/2)^2=25/4所以x+3/2=±5/2所以x=1或-4

您好：2x的平方减7x减6=0x²-7/2x=3x²-7/2x+49/16=3+49/16(x-7/4)²=97/16x-7/4=±√97/4x=7/4±√97/4如果本

2x²-2x-3=0x²-x-3/2=0x²-x+(1/2)²-(1/2)²-3/2=0(x-1/2)²=7/4x-1/2=±√7/2x=(

X²+2X-99=0X²+2X=99两侧同时加上1得：X²+2X+1=99+1X²+2X+1=100(X+1)²=100X+1=±√100X+1=±1

4x²-x-9=0x²-1/4*x-9/4=0x²-1/4*x+1/64=9/4+1/64(x-1/8)²=145/64x-1/8=±√145/8√∴x=1/8

用配方法解方程:2x²+x-6=02x²+x-6=2(x²+x/2)-6【第一步把二次项系数变为1】=2[(x+1/4)²-1/16]-6【第二步配一次项系数的

4X平方减3X减1等于04(x²-3/4x）=14(x-3/8)²=1+9/16(x-3/8)²=25/64x-3/8=±5/8x1=1x2=-1/4

x-2x+1-1-2=(x-1)-3=0所以（x-1）=3求x=±√3+1

4x^2+8x+1=0(2x)^2+4x+1+4x=0(2x+1)^2+4x=0一步步解出来就OK了.

（x+1）×（x+6）再答：错了，是减号再答：（x-1）（x-6）再问：不对吧再答：再答：第一次错了，换成减号就对了，答案是x等于1或者6再答：(^_^)(^_^)

x^2-4x+1=0x^2-4x+1+3=3(x-2)^2=3x-2=±√3x=2±√3

x^2+x-1=0x^2+x=1(x^2+x+1/4-1/4)=1(x+1/2)^2=5/4x+1/2=±(√5)/2x1=(1+√5)/2x2=(1-√5)/2

3x^2-12x-21=0x^2-4x-7=0移项得：x^2-4x=7,配方得：x2-4x+4=7+4,即（x-2）^2=11,开方得：x-2=±√11,∴原方程的解是：x1=2+√11x2=2-√1

再答：对不对？再问：谢谢，对了

原式等于x^2-2x+1-3=0(x-1)^2-3=0(x-1+根号3)(x-1-根号3)=0x=1+根号3或x=1-根号3