2(x-3)方+2(x方-1)=4x+1要过程

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2(x-3)方+2(x方-1)=4x+1要过程
2(x-3)方+2(x方-1)=4x+1要过程

2(x-3)方+2(x方-1)=4x+1要过程
2(x-3)方+2(x方-1)=4x+1
2(x方-6x+9)+2x方-2=4x+1
4x方-12x+16=4x+1
4x方-16x+16=1
4(x方-4x+4)=1
4(x-2)方=1
(x-2)方=1/4
x-2=±1/2
x=2.5,x=1.5

2(x^2-6x+9)+2x^2-2=4x+1
2x^2-12x+9+2x^2-2=4x+1
4x^2-16x=-8
x^2-4x=-2
...

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2(x^2-6x+9)+2x^2-2=4x+1
2x^2-12x+9+2x^2-2=4x+1
4x^2-16x=-8
x^2-4x=-2
(x-2)^2=-2+4
x-2=±根号2
所以x=±根号2+2
(“^”是平方)

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2(x-3)^2+2(x^2-1)=4x+1
展开得:4x^2-16x+15=0
所以 Δ=16^2-4×4×15=16
由二次函数的公式可得 x=(16+或-根号下16)/(2×4)=1.5 或2.5

2(x方-6x+9)+2x方-2=4x+1
2x方-12x+18+2x方-2=4x+1
4x方-12x+16=4x+1
4x方-16x+15=0
(2x-5)(2x-3)=0
x=5/2(二分之五)或3/2(二分之三)

2(x²-6x+9)+2(x²-1)=4x+1
4x²-16x+15=0
(2x-3)(2x-5)=0
X=1.5或x=2.5

2(x^2-6x+9)+2x^2-2=4x+1
-12x+18-2=4x+1
16x=15
x=15/16