A= (x+1)^2-(x-2)^2-3(x+1)(x-1) Question A= (x+1)^2-(x-2)^2-3(x+1)(x-1) in progress 0 Môn Toán Gerda 4 years 2020-11-20T02:13:13+00:00 2020-11-20T02:13:13+00:00 2 Answers 53 views 0
Answers ( )
Đáp án:
$A = (x + 1)² – (x – 2)² – 3(x + 1)(x – 1)$
$A = x² + 2x + 1 – (x² – 4x + 4) – 3(x² – 1)$
$A = x² + 2x + 1 – x² + 4x – 4 – 3x² + 3$
$A = -3x² + 6x $
$A = -3x(x – 2)$
Khánh-;-