Question

Phân tích đa thức thành nhân tử :

a) 4x⁴ + 81

b) x⁷ + x² + 1

Answer 1

a)4x⁴+36x²+81-36x²

=(4x⁴+36x²+81)-63x²

=(2x²+9)²-36x²

=(2x²+9-6x)(2x²+9+6x)

Answer 2

Bạn kia chưa làm hết mk làm nốt :V

\(A=x^7+x^2+1\)

\(A=x^7+x^2+1+x-x\)

\(A=\left(x^7-x\right)+\left(x^2+x+1\right)\)

\(A=x\left(x^6-1\right)+\left(x^2+x+1\right)\)

\(A=x\left(x^3+1\right)\left(x^3-1\right)+\left(x^2+x+1\right)\)

\(A=x\left(x^2+x+1\right)\left(x^3-1\right)+\left(x^2+x+1\right)\)

\(A=\left(x^4-x\right)\left(x^2+x+1\right)+1\left(x^2+x+1\right)\)

\(A=\left(x^2+x+1\right)\left[\left(x^4-x\right)+1\right]\)

\(A=\left(x^2+x+1\right)\left(x^4-x+1\right)\)