Bonsoir,
Ex
C (3 ; 7) et D (9 ; 11)
a= (11-7)/(9-3)
a=4/6= 2/3
Donc f(x)= 2/3 x + b
f(3)=7
2/3(3)+b= 7
b= 7-2
b= 5
f(x)= 2/3 x +5
Ex
f (x) = -5x +7
a) calcule f(2) et f(-2)
f(2)= -5(2)+7
f(2)= -10+7
f(2)= -3
f(-2) = -5(-2)+7
f(-2)= 10+7
f(-2)= 17
g(1)= 7(1)+4
g(1)= 11
g(x) = 7x + 4
g(0) = 7(0)+4
g(0)= 4