Giúp mik bài này với mik cho 5sao+ctlhn ạ

`@ T = ( x + 1 )( x^6 - x^5 + x^4 - x^3 + x^2 - x + 1 )`

`= x( x^6 - x^5 + x^4 - x^3 + x^2 - x + 1 ) + 1( x^6 - x^5 + x^4 - x^3 + x^2 - x + 1 )`

`= x^7 - x^6 + x^5 - x^4 + x^3 - x^2 + x + x^6 - x^5 + x^4 - x^3 + x^2 - x + 1`

`= x^7 + ( x^6 - x^6 ) + ( x^5 - x^5 ) + ( x^4 - x^4 ) + ( x^3 - x^3 ) + ( x^2 - x^2 ) + ( x - x ) + 1`

`= x^7 + 1`

`@ T(-2) = ( -2 )^7 + 1`

`= -128 + 1`

`= -127`