a1=q*ao=q
a2=qa1=q²ao=q²
a3=q*a2=q³*ao=q³
-----------------------------Se observa ca:
an=q^n =>
a(n+1)=q^(n+1)
Introducem in relatia Ddata valorile lui an-1 ,an, an+1
q(n+1)=3*q^n -2*q^(n-1) =>
q*q^n=3*q^n-2*q^n/q aduci la acelasi numitor
q²*q^n=3*q*q^n-2*q^n Simplificam prin q^n
q²=3q-2 =>
q²-3q+2=0 REzolvi ecuatia si obtii
q1=1 nu se accepta
q2=2
