解方程x^2+2x+2=6/(x+1)^2

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解方程x^2+2x+2=6/(x+1)^2

解方程x^2+2x+2=6/(x+1)^2
解方程x^2+2x+2=6/(x+1)^2

解方程x^2+2x+2=6/(x+1)^2
x^2+2x+2=6/(x+1)^2
(x+1)^2 +1=6/(x+1)^2
设(x+1)^2=y
y+1=6/y
y^2+y-6=0
(y+3)(y-2)=0
y=-3(舍去)
y=2
(x+1)^2=2
x+1=±√2
x1=√2-1
x1=-√2-1

(x+1)²1=6/(x+1)²
设y=(x+1)²
则有:y+1=6/y
y²+y-6=0
(y+3)(y-2)=0
y1=2, y2=-3<0(不合题意,舍去)
∴ ( x+1)²=2

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(x+1)²1=6/(x+1)²
设y=(x+1)²
则有:y+1=6/y
y²+y-6=0
(y+3)(y-2)=0
y1=2, y2=-3<0(不合题意,舍去)
∴ ( x+1)²=2
x+1=±√2
x1=-1+√2
x2=-1-√2
经检验:x1和x2都是原方程的解。

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x^2+2x+2=6/(x+1)^2
(x+1)^2+1=6/(x+1)^2
分母不为零,x+1≠0,x≠-1
两边同乘以(x+1)^2
(x+1)^4+(x+1)^2=6
(x+1)^4+(x+1)^2-6=0
{(x+1)^2+3} {(x+1)^2-2} = 0
∵{(x+1)^2+3}恒大于0
∴(x+1)^2-2 = 0
(x+1)^2=2
x=-1±根号2

(x^2+2x+2)(x^2+2x+1)-6=0,
设x^2+2x+1=a,
则a(a+1)-6=0,
a=2,
则(x+1)^2=2,
x等于根号2减1