Question

(x-2)(x-3)-(x+1)(x-6)

help me cần gấpp <3

Answer 1

`(x-2)(x-3)-(x+1)(x-6)`

`=x^2-3x-2x+6-x^2+6x-x+6`

`=(x^2-x^2)-(3x+2x-6x+x)+(6+6)`

`=12`

Answer 2

\(\left(x-2\right)\left(x-3\right)-\left(x+1\right)\left(x-6\right)\)

\(\Leftrightarrow x^2-3x-2x+6-\left(x^2-6x+x-6\right)\)

\(\Leftrightarrow x^2-3x-2x+6-\left(x^2-5x-6\right)\)

\(\Leftrightarrow x^2-3x-2x+6-x^2+5x+6\)

\(\Leftrightarrow0+12\)

\(\Leftrightarrow12\)

Answer 3

`(x-2)(x-3)-(x+1)(x-6)`

`=x^2 -3x -2x +6 -x^2 +6x-x-6`

`=-(3x+2x-6x+x)+(6+6)+(x^2 - x^2)`

`=12`

Vậy chứng tỏ đa thức này ko phụ thuộc vào biến x