Respuesta :

enika
f(x+h) = 2(x+h) +3= 2x + 2h +3
f(x) = 2x + 5

f(x+h) - f(x) = 2x + 2h + 3- 2x - 3= 2h

[f(x+h) - f(x)]/h = 2h/h = 2