Bonjour
Je suppose qu’il faut factoriser ??
Identité remarquable :
a^2 - b^2 = (a - b)(a + b)
b=81-(x-2/5)²
B = 9^2 - (x - 2/5)^2
B = (9 - x + 2/5)(9 + x - 2/5)
B = (-x + 45/5 + 2/5)(x + 45/5 - 2/5)
B = (-x + 47/5)(x + 43/5)
c=(x-1)²-1/4
C = (x - 1)^2 - (1/2)^2
C = (x - 1 - 1/2)(x - 1 + 1/2)
C = (x - 2/2 - 1/2)(x - 2/2 + 1/2)
C = (x - 3/2)(x - 1/2)
d=16/49-(1-3x)²
D = (4/7)^2 - (1 - 3x)^2
D = (4/7 - 1 + 3x)(4/7 + 1 - 3x)
D = (3x + 4/7 - 7/7)(-3x + 4/7 + 7/7)
D = (3x - 3/7)(-3x + 11/7)
e=(1/3-2x)²-4/9
E = (1/3 - 2x)^2 - (2/3)^2
E = (1/3 - 2x - 2/3)(1/3 - 2x + 2/3)
E = (-2x - 1/3)(-2x + 3/3)
E = (-2x - 1/3)(-2x + 1)
