Exercice 2 :
A = (x + 1)(x + 1) - (x² - x)
A = x² + x + x + 1 - (x² - x )
A = x² + 2x + 1 - x²+ x
A = 2x + 1 + x
A = 3x + 1
B = (x - 7)(8 - 2x) - 5 + 3(x² - 4) + (x² - 3)
B = 8x -2x² - 56 + 14x - 5 + 3x² - 12 + x² -3
B = -2x² + 3x² + 8x - 56 - 5 -12 -3
B= x² + 8x -75