Question

2(x-1)²-8=0 , x²-8x-2=0, x²-6=7x, 2x²-6x+1=0, 3x²+8x-2=0.

解方程，过程加答案，谢谢。

Answer 1

1. （x-1)²=4 x=3或-1
2. Δ=64+8=72 x=4±3倍根号2
3. Δ=49+24=73 x=（7±根号73）/2
4. Δ=36-8=28 x=(3±根号7）/2
5 Δ=64+24=88 x=（4±根号22）/3

Answer 2

2(x-1)²-8=0 ,
(x-1)²-4=0
(x-1-2)(x-1+2)=0
(x-3)(x+1)=0
x=3或x=-1

x²-8x-2=0,
x²-8x+16-16-2=0
(x-4)²-18=0
(x-4-3√2)(x-4+3√2)=0
x=4+3√2或x=4-3√2

x²-6=7x,
x²-7x-6=0
x²-7x+49/4-49/4-6=0
(x-7/2)²-73/4=0
(x-7/2)²-73/4=0
(x-7/2-√73/2)(x-7/2+√73/2)=0
x=7/2+√73/2或x=7/2-√73/2

2x²-6x+1=0
x²-3x+1/2=0
x²-3x+9/4-9/4+1/2=0
(x-3/2)²-7/4=0
(x-3/2-√7/2)(x-3/2+√7/2)=0
x=3/2+√7/2或x=3/2-√7/2

3x²+8x-2=0
x²+8x/3-2/3=0
x²+8x/3+16/9-16/9-2/3=0
(x+4/3)²-22/9=0
(x+4/3-√22/3)(x+4/3+√22/3)=0
x=-4/3+√22/3或x=-4/3-√22/3