已知函数f(x)=3x²-5x+2,求f(f(x))=

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已知函数f(x)=3x²-5x+2,求f(f(x))=

因为f(x)=3x²-5x+2=(3x-2)*(x-1)
f(f(x))=【3(3x²-5x+2)-2】*【(3x²-5x+2)-1】=27x^4-90x^3+96x^2-35x+4

f(f(x))=3f(x)²-5f(x)+2
=3(3x²-5x+2)²-5(3x²-5x+2)+2
=27x^4-90x^3+96x^2-35x+4