函数2f(x)+x^2f(1/x)=(3x^2-x^2+4x+3)/(x+1),求f(x)

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函数2f(x)+x^2f(1/x)=(3x^2-x^2+4x+3)/(x+1),求f(x)

函数2f(x)+x^2f(1/x)=(3x^2-x^2+4x+3)/(x+1),求f(x)
函数2f(x)+x^2f(1/x)=(3x^2-x^2+4x+3)/(x+1),求f(x)

函数2f(x)+x^2f(1/x)=(3x^2-x^2+4x+3)/(x+1),求f(x)
2f(x)+x^2f(1/x)=(3x³-x²+4x+3)/(x+1) (1)
2x²f(1/x)+f(x)=(3-x+4x²+3x³)/(x+1) (2) 用1/x代替x并化简
(1)*2-(2) 得
3f(x)=(3x³-6x²+9x+3)/(x+1)
f(x)=(x³-2x²+3x+1)/(x+1)

u

2f(x)+x^2f(1/x)=(3x^2-x^2+4x+3)/(x+1)
2f(x)+x^2f(1/x)=(2x^2+4x+3)/(x+1) (1)
2f(1/x)+(1/x)^2f(1/1/x)=(2(1/x)^2+4(1/x)+3)/((1/x)+1)
2x^2f(1/x)+f(x)=(3x^2+4x+2)/((1/x)+1)
2x^2f(1/x)+f(x)=...

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2f(x)+x^2f(1/x)=(3x^2-x^2+4x+3)/(x+1)
2f(x)+x^2f(1/x)=(2x^2+4x+3)/(x+1) (1)
2f(1/x)+(1/x)^2f(1/1/x)=(2(1/x)^2+4(1/x)+3)/((1/x)+1)
2x^2f(1/x)+f(x)=(3x^2+4x+2)/((1/x)+1)
2x^2f(1/x)+f(x)=x(3x^2+4x+2)/(x+1) (2)
(1)*2-(2)
3f(x)=2(2x^2+4x+3)/(x+1)-x(3x^2+4x+2)/(x+1)
f(x)=(4x^2+8x+6-3x^3-4x^2-2x)/3(x+1)
f(x)=(6x+6-3x^3)/3(x+1)
f(x)=(2x+2-x^3)/(x+1)
f(x)=(-x^3+2x+2)/(x+1)

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