Réponse :
Explications étape par étape
a^2 - b^2 = (a - b)(a + b)
Bonsoir
Factoriser :
9x^2 - 49
= (3x)^2 - 7^2
= (3x - 7)(3x + 7)
(5/3 x + 2/3)^2 - (3/2 x - 3/5)^2
= (5/3 x + 2/3 - 3/2 x + 3/5)(5/3 x + 2/3 + 3/2 x - 3/5)
= (10/6 x - 9/6 x + 10/15 + 9/15)(10/6 x + 9/6 x + 10/15 - 9/15)
= (1/6 x + 19/15)(19/6 x + 1/15)
= (x/6 + 19/15)(19x/6 + 1/15)
Developper :
(3/5 z - 7/5 t)(3/5 z + 7/5 t)
= (3/5 z)^2 - (7/5 t)^2
= 9/25 z^2 - 49/25 t^2
= 9z^2/25 - 49t^2/25
(x/3 + V7)(x/3 - V7)
= (x/3)^2 - (V7)^2
= x^2/9 - 7
