Ex 1 : (* = multiplié)
A = 12x² + (4x + 5)²
A = 12x² + ((4x)² + 2*4x*5 + 5²)
A = 12x² + 16x² + 40x + 25
A = 28x² + 40x + 25
B = 7x - (6x + 2)²
B = 7x - ((6x)² + 2*6x*2 + 2²)
B = 7x - (36x² + 24x + 4)
B = 7x - 36x² - 24x - 4
B = - 36x² -17x -4
C = -16x² - (4x - 1)(4x + 1)
C = -16x² - ((4x)² - 1²)
C = -16x² - (16x² - 1)
C = -16x² - 16x² + 1
C = -32x² + 1
D = (6x - 4)² + (2x - 6)²
D = (6x)² - 2*6x*4 + 4² + ((2x)² -2*2x*6+6²
D = 36x² -48x + 16 + (4x² - 24x + 36)
D = 36x² -48x + 16 + 4x² -24x + 36
D = 40x² - 72x + 52
