Bonjour,
Ex5
(a+b)(c+d) = ac + ad + bc + bd
A = 8x² + 2x + 12x + 3 = 8x² + 14x + 3
B = 5x² - 5x + 6x - 2 = 5x² + x - 2
C = 10y - 2y² - 5 + y = -2y² + 11y -5
D = 3 (8a² - 32a - 4a + 16) = 3 (8a² - 36a + 16) = 24a² - 108a + 48
E = (2x + 1) (4x + 3) / 100 = (8x² + 6x + 4x +3)/100 = (8x² + 10x + 3)/100 = 8x²/100 + 10x/100 + 3/100 = 2x²/25 + x/10 + 3/100
Ex6
G = (2x + 3) (x - 1 + 4x + 1) = (2x + 3) (5x) = 5x (2x + 3)
H = (5x + 2) (3x - 1 - (4x +1)) = (5x + 2) ( 3x - 1 - 4x - 1) = (5x +2) ( -x - 2) = - (5x + 2) (x +2)
I = (2y - 1) (2y - 1 + y + 2) = (2y -1) ( 3y + 1)
J = (3x +2) (7x - 5 - (3x +2)) = (3x +2) ( 7x - 5 - 3x - 2) = (3x + 2) (4x - 7)
