bonsoir
courbe rouge
h ( 2 ) = 4 et h ( - 2 ) = 1
( 1 - 4 ) / ( - 2 - 2 ) = - 3 /-4
ax = 3 x /4
h ( 2) = 4
2 * 3/4 + b = 4
b = 4 - 6/4 = 16 /4 - 6 /4 = 10 /4 = 5 /2 = 2.5
h (x ) = 3 x /4 + 2.5
d'où h ( - 2 ) = - 2 * 3/4 + 2.5 = - 6 /4 + 2.5 = - 1.5 + 2.5 = 1
courbe noire
k ( 1 ) = - 1 et g ( - 2 ) = 3
( 3 + 1 ) / ( - 2 - 1 ) = 4 / - 3 = - 4/ 3
ax = - 4 x /3
k ( 1 ) = - 1
1 * - 4/3 + b = - 1
b = - 1 + 4/3 = 1 /3
k (x) = - 4 x /3 + 1/3
d'où k ( - 2 ) = - 2 * - 4/3 + 1/3 = 8/3 + 1/3 = 9/3 = 3
3 x /4 + 2.5 < - 4 x /3 + 1/3
9 x /12 + 36 x /12 < 4/12 - 30/12
45 x < - 26
x < - 26/45
