`(x+1)^2-(x-1)^2-3(x-3)(x+3)` rut gon

2 bình luận về “`(x+1)^2-(x-1)^2-3(x-3)(x+3)` rut gon”

1. (x + 1)² – (x – 1)² – 3(x – 3) (x + 3)

   = (x + 1 – x + 1) (x + 1 + x – 1) – 3(x² – 9)

   = 2 . 2x – 3x² + 27

   = -3x² + 4x +27

   $#Ched$

   $\text{ Gửi Tus, xin ctrl hay nhất ak }$

   Trả lời
2. (x+1)^2 – (x-1)^2 – 3(x-3)(x+3)

   = [(x+1) – (x-1)][(x+1) + (x-1)] – 3(x^2 – 3^2)

   = (x +1 – x +1)(x+1 + x -1) – 3(x^2 – 9)

   = 2 . 2x – 3x^2 + 27

   = 4x – 3x^2 + 27

   #HPHG

    

   Trả lời