Réponse :
Explications étape par étape
Bonjour
Résoudre dans R les équations suivantes.
a) 5x2 - 6x=0
x(5x - 6) = 0
x = 0 ou 5x - 6 = 0
x = 0 ou 5x = 6
x = 0 ou x = 6/5
b) (2x + 1)(x + 4) + (x + 4)(3 – 5x) = 0
(x + 4)(2x + 1 + 3 - 5x) = 0
(x + 4)(-3x + 4) = 0
x + 4 = 0 ou -3x + 4 = 0
x = -4 ou 3x = 4
x = -4 ou x = 4/3
c) (x - 7)(3x – 5) - (9x - 4)(x – 7) = 0
(x - 7)(3x - 5 - 9x + 4) = 0
(x - 7)(-6x - 1) = 0
x - 7 = 0 ou -6x - 1 = 0
x = 7 ou 6x = -1
x = 7 ou x = -1/6
d) 4x2 + 8x + 4 = 0
(2x)^2 + 2 * 2x * 2 + 2^2 = 0
(2x + 2)^2 = 0
2x + 2 = 0
2x = -2
x = -2/2
x = -1
e) (4x – 7)(9x + 5) = (8x – 3)(4x – 7)
(4x - 7)(9x + 5 - 8x + 3) = 0
(4x - 7)(x + 8) = 0
4x - 7 = 0 ou x + 8 = 0
4x = 7 ou x = -8
x = 7/4 ou x = -8