SVP SES URGENT SES POUR DEMAIN

Ex 53
a)
F = (3x-5)²-(3x-5)(x+4)
F = (9x²-30x+25)-(3x²+12x-5x-20)
F = 9x²-30x+25-(3x²+7x-20)
F = 9x²-30x+25-3x²-7x+20
F = 6x²-37x+45

b)
F = (3x-5)(3x-5-x-4)     on a mis 3x-5 en facteur
F = (3x-5)(2x-9)

c) F(1) = 6x1-37x1+45 = 51-37 = 14
F(4,5) = (3*4,5-5)(2x4,5-9) = (13,5-5)(9-9) = 8,5x0 = 0