Bonjour,
Résoudre:
a) (2x+1)(3x+10)-(2x+1)(5x-8)= 0
(2x+1)(3x+10-5x+8)= 0
(2x+1)(-2x+18)= 0
2x+1= 0 ou -2x+18= 0
2x= -1 -2x= -18
x= - 1/2 x= -18/-2= 9
S= { - 1/2; 9 }
b) (4x-5)(9x+7)-(8x-3)(4x-5)= 0
(4x-5)(9x+7-8x+3)= 0
(4x-5)(x+10)= 0
x= 5/4 ou x= -10
S= { -10; 5/4 }.
c) (5x-2)(3x+4) - (2-5x)(2x+7)= 0
(5x-2)(3x+4) + (5x-2)(2x+7)= 0
(5x-2)(3x+4+2x+7)= 0
(5x-2)(5x+11)= 0
x= 2/5 ou x= - 11/5
S= { - 11/5; 2/5 }
d) (7x-4)(5x+1)+(7x-4)(3x-2)= 0
(7x-4)(5x+1+3x-2)= 0
(7x-4)(8x-1)= 0
x= 4/7 ou x= 1/8
S= { 1/8; 4/7 }.
