A = (2x - 3)² + (5x - 1)(3x + 1)
A = [(2x)² - 2*2x*3 + 3²] + [5x*3x + 5x*1 - 1*3x -1*1]
A = 4x² -12x + 9 + 15x² + 5x - 3x - 1
A = 19x² - 15x + 5x + 8
A = 19x² - 10x + 8
B = 2 (3 - x) - (5x - 7)
B = 2*3 + 2*(-x) - 5x + 7
B = 6 - 2x - 5x + 7
B = - 7x + 13
C = (2x + 3)² + (3x - 1)(3x + 1)
C= [ (2x)² + 2*2x*3 + 3²] + [3x*3x + 3x*1 -1*3x - 1*1]
C = 4x² + 12x + 9 - 9x² + 3x - 3x - 1 ( 3x - 3x on les barre)
C = - 5x² + 12x + 8
D = 4 ( 1 - 4x)(3x + 5)
D = 4 ( 1*3x + 1*5 - 4x*3x - 4x*5
D = 4 ( 3x + 5 - 12x² - 20x
D = 4( - 12x² - 17x + 5)
D = 4*(-12x²) + 4*(-17x) + 4*5
D = - 48x² - 68x + 20
E = 2x² - ( 12x -2)( 2 - 3x )
E = 2x² - [12x*2 + 12x*(-3x) - 2*2 - 2*(-3x)]
E = 2x² - ( 24x - 36x² - 4 + 6x)
E = 2x² - 24x + 36x² + 4 - 6x
E = 38x² - 30x + 4
