Bonjour
L = (1 - 2n)² - (3n + 2) (3n - 2)
L = 1 - 4n + 4n² - (9n² - 4)
L = 1 - 4n + 4n² - 9n² + 4
L = - 5n² - 4n + 5
M = 3 (4x + 1) (x + 1) + (2 - x/2)²
M = 3 (4x² + 4x + x + 1) + 4 - 4x/4 + x²/4
M = 12x² + 12x + 3x + 3 + 4 - 4x/4 + x²/4
M = 48x²/4 + x²/4 + 12x + 3x - 2x + 7
M = 49x²/4 + 13x + 7
N = (n + 5) (n - 5) - 1/3 (1 - 3n)²
N = n² - 25 - 1/3 (1 - 6n + 9n²)
N = n² - 25 - 1/3 + 6/3n - 9/3n²
N = n² - 25 - 1/3 + 2n - 3n²
N = - 2n² + 2n - 75 /3 - 1/3
N = - 2n² + 2n - 76/3
