Đáp án:
`-2x^5+2x+2`
Giải thích các bước giải:
`\qquad (x+1)*(1 +x - x^2 + x^3 -x^4)-(x-1)*(1 +x+x^2 +x^3 +x^4)`
`=x(1 +x - x^2 + x^3 -x^4)`
`+1.(1 +x - x^2 + x^3 -x^4)`
`-x(1 +x+x^2 +x^3 +x^4)`
`+1.(1 +x+x^2 +x^3 +x^4)`
`=x+x^2-x^3+x^4-x^5+1+x-x^2+x^3-x^4`
`-x-x^2-x^3-x^4-x^5+1+x+x^2+x^3+x^4`
`=(-x^5-x^5)+(x^4-x^4-x^4+x^4)+(-x^3+x^3-x^3+x^3)+(x^2-x^2-x^2+x^2)+(x+x-x+x)+1+1`
`=-2x^5+2x+2`
Vậy: `(x+1)*(1 +x - x^2 + x^3 -x^4)-(x-1)*(1 +x+x^2 +x^3 +x^4)=-2x^5+2x+2`
