2x^2-6x-1=0还有根号2x^2-4x=4根号2(x-2)^2-4(x-2)^2=-4

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2x^2-6x-1=0还有根号2x^2-4x=4根号2(x-2)^2-4(x-2)^2=-4

2x^2-6x-1=0还有根号2x^2-4x=4根号2(x-2)^2-4(x-2)^2=-4
2x^2-6x-1=0
还有根号2x^2-4x=4根号2
(x-2)^2-4(x-2)^2=-4

2x^2-6x-1=0还有根号2x^2-4x=4根号2(x-2)^2-4(x-2)^2=-4
2x²-6x=1
x²-3x=1/2
x²-3x+9/4=11/4
(x-3/2)²=11/4
x=3/2+√11/2 x=3/2-√11/2
2、2x²-4x=32
x²-2x=16
x²-2x+1=17
(x-1)²=17
∴x=1+√17 x=1-√17
(x-2)²-4(x-2)+4=0
(x-2-2)²=0
x=4

2x²-6x-1=0
Δ=36+8=44
x=(6±2√11)/4

2x²-4x=4√2
x²-2x+1=2√2+1
(x-1)²=2√2+1
x-1=±√(2√2+1)
x=1±√(2√2+1)

(x-2)²-4(x-2)²=-4
3(x-2)²=4
(x-2)²=4/3
x-2=±2√3/3
x=2±2√3/3

直接用万能公式法(-b -根b方-4ac)/2a