Question

Thực hiện phép tính :

(x -3 )² - x² + 10x - 7

 

Answer 1

`@` `\text {Ans}`

`\downarrow`

`(x-3)^2 - x^2 + 10x - 7`

`= x^2 - 6x + 9 - x^2 + 10x - 7`

`= (x^2 - x^2) + (-6x + 10x) + (9-7)`

`= 4x + 2`

Answer 2

\(\left(x-3\right)^2-x^2+10x-7\)

\(=\left(x^2-6x+9\right)-x^2+10x-7\)

\(=\left(x^2-x^2\right)-\left(6x-10x\right)+\left(9-7\right)\)

\(=4x+2\)

\(=2\left(2x+1\right)\)