Question

rút gọn biểu thức 

N=(x²-3x+1)+2(x²+3x+1)(3-x-x²)+(3-x-x²)²

Answer 1

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

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

Answer 2

đúng thì

Answer 3

Ta có : x^2-3x+1+(2x^2+6x+2)(3-x-x^2)+(3-x-x^2)^2

x^2-3x+1+6x^2-2x^3-2x^4+18x-6x^2-6x^3+6-2x-2x^2+9-x^2-x^4

22+(x^2+6x^2-6x^2-2x^2-x^2)+(-3x+18x)+(2x^3-6x^3)+(-2x^4-x^4)

22-3x^2+15x-4x^3-3x^4