Réponse :
{U0 = 1
{Un+1 = 1/(3+2Un)
calculer U3
U1 = 1/(3+2U0) = 1/(3+2) = 1/5
U2 = 1/(3 + 2U1) = 1/(3 + 2/5) = 1/17/5 = 5/17
U3 = 1/(3 + 2U2) = 1/(3 + 10/17) = 1/61/17 = 17/61
Explications étape par étape :
