bjr
g(x) = x(2 - 5x) + 7
pour calculer g(-1) on remplace x par -1 dans x(2 - 5x) + 7
g(-1) = (-1)[(2 - 5(-1)] + 7
= (-1) ( 2 + 5)) + 7
= (-1) x 7 + 7
= -7 + 7
g(-1) = 0
g(0) = 0*(2 -5*0) + 7
= 0 + 7
g(0) = 7
g(1/3) = (1/3)[2 - 5(1/3)] + 7
= (1/3)(2 - 5/3) + 7
= (1/3)(6/3 - 5/3) + 7
= (1/3)(1/3) + 7
= 1/9 + 7
= 1/9 + (7 x 9)/9
= 1/9 + 63/9
g(1/3) = 64/9
g(2/5) = (2/5)[2 -5(2/5)] + 7
= (2/5)(2 - 2) + 7
= (2/5)*0 + 7
g(2/5) = 7
