Développer,réduire,ordonner x(3x-2)-(x+1)(x-2)

Bonjour, 

x(3x - 2) - (x + 1)(x - 2)
= 3x² - 2x - (x² - 2x + x - 2)
= 3x² - 2x - x² + 2x - x + 2
= 2x² - x + 2

Bonjour

♤ On a :

A = x(3x-2)-(x+1)(x-2)
A = x×3x + x×(-2) - (x×x + x×(-2) +1×x + 1×(-2))
A = 3x² -2x - (x² - 2x + x -2)
A = 3x² - 2x - x² + 2x - x + 2
A = 2x² - x + 2