Câu 3: a: \(f\left(x\right)=3x^4-6x^3-6x+9\)\(G\left(x\right)=-2x^4+4x^3+2x^2+9x-10\)b: \(f\left(x\right)+g\left(x\right)=x^4-2x^3+2x^2+3x-1\)Câu trả lời: Câu 3: a: \(f\left(x\right)=3x^4-6x^3-6x+9\)\(G\left(x\right)=-2x^4+4x^3+2x^2+9x-10\)b: \(f\left(x\right)+g\left(x\right)=x^4-2x^3+2x^2+3x-1\)