胖胖猪理财 倒闭:两道分式方程:(1/x-2)+(2/x+2)=1/2

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两道分式方程:
1)(1/x-2)+(2/x+2)=1/2

2)[1/x(x+2)]-[2/x(x-2)]=1/2

解:1.1/(x-2)+2/(x+2)=1/2
(x+2)/[(x+2)(x-2)]+(2x-4)/[(x+2)(x-2)]=1/2
(3x-2)/(x^2-4)=1/2
6x-4=x^2-4
x^2-6x=0
x(x-6)=0
x=0,6
2.[1/x(x+2)]-[2/x(x-2)]=1/2
(x-2)/[x(x+2)(x-2)]-(2x+4)/[x(x+2)(x-2)]=1/2
(-x-6)/x(x+2)(x-2)=1/2
(-x-6)/x(x^2-4)=1/2
(-x-6)/(x^3-4x)=1/2
-2x-12=x^3-4x
x^3-2x+12=0
x^3+8+2x+4=0
(x+2)(x^2+4-2x)+2(x+2)=0
(x+2)(x^2-2x+6)=0
∴x+2=0,x=-2
∵x^2-2x+6>0
∴x=-2

1.两边同乘2(x+2)(x-2)
2(x+2)+4(x-2)=x^2-4
化简为x^2-6x=0
x=0或x=6
2.两边同乘2x(x+2)(x-2)
2(x-2)-4(x+2)=x(x+2)(x-2)