Ta phân tích như sau e nhé :)
\(3x^4+3x^2+3-\left(x^4+x^2+2x+1+2x^2\left(x+1\right)\right)\)
\(=3x^4+3x^2+3-\left(x^4+x^2+2x+1+2x^3+2x^2\right)\)
\(=2x^4-2x^3-2x+2=2\left[x^3\left(x-1\right)-\left(x-1\right)\right]=2\left(x-1\right)^2\left(x^2+x+1\right)\)