Hello,
[tex]A = (x - 3)(-x + 5)
A = (4 - 3)(-4 + 5)
A = 1 \times 1 = 1[/tex]
[tex]B = x^2 + 3x - 12
B = (-3)^2 + 3 \times (-3) - 12
B = 9 - 9 - 12
B = -12[/tex]
[tex]C = 4x^2 - 5x - 6
C = 4 \times (-2)^2 - 5 \times (-2) - 6
C = 4 \times 4 + 10 - 6
C = 16 + 10 - 6
C = 26 - 6
C = 20[/tex]
Si tu as des questions, n'hésite pas ! =)
