1)a. Aire triangle rectancle = (coté adj×coté opposé)/2
A(adn) = (AD×DN)/2 or DN = DC-1 = 6-1 = 5
A(adn) = (4×5)/2 = 10cm²
A(abm) = (AB×BM)/2
A(abm) = (6×1)/2 = 3cm²
1)b.A(adn) = (AD×DN)/2 or DN = DC-1 = 6-2 = 4
A(adn) = (4×4)/2 = 8cm²
A(abm) = (AB×BM)/2
A(abm) = (6×2)/2 = 6cm²
2)a. f(x) = [4(6-x)]/2 = (24-4x)/2 = -2x+12
g(x) = 6x/2 = 3x
2)b. 4 ≤ x ≤ 0
2)c. Il faut calculer
f(2,5) =-2×2,5+12
g(2,5) = 3×2,5
2)d. Il faut calculer:
f(x) = 6
-2x+12 = 6 => 6 = 2x => x=3
2)e. g(x) = 6 => 3x = 6 => x = 2
3) f est une fonction affine car de la forme y = ax+b.
g est une fonction linéaire car de la forme y = ax.
