Bonjour,

6x²-7x-3

Calculer:

k(0)= 6(0)²-7(0)-3= -3

k(-1)= 6(-1)²-7(-1)-3= 6+7-3= 10

k(3/2)=  6(3/2)²-7(3/4)-3= 6(9/4)-21/3-3= 54/4-21/3-3= (54x3-21x4-3x12)/ 12= 42/12= 7/2

k(-1/3)= 6(-1/3)²-7(-1/3)-3= 6/9+7/3-3= (6+7x3-3x9)/9= 0

Résoudre 6x²-7x-3=0

On factorise et on obtient :

(2x-3)(3x+1)= 0  

2x-3= 0  ou  3x+1= 0

x= 3/2           x= -1/3

S= { -1/3 ; 3/2 }