Bonjour, pourriez vous m'aider pour une question en maths (suite) svp merci d'avance!

Bonjour,

Uo = 1

Un+1 = –2 –2Un

U1 = –2 – 2×Uo

U1 = –2 – 2×1

U1 = –4

U2 = –2 – 2×U1

U2 = –2 – 2×(–4)

U2 = –2 + 8

U2 = 6

U3 = –2 – 2×U2

U3 = –2 – 2×6

U3 = –2 –12

U3 = –14