a1+a1q=2(1/a1+1/a1q)
a1(1+q)=2(1+q)/a1q
a1^2q=2 (1)
a1(q^2+q^3+q^4)=64(q^2+q+1)/a1q^4
a1^2q^6=64 (2)
(2)/(1)
q^5=32 q=2 a1=1
an=2^(n-1)
2. bn=(an+1/an)^2=4^(n-1)+2+1/4^(n-1)
Sn=(1-4^n)/(1-4)+2n+[1-(1/4)^n]/(1-1/4)
=(4^n-1)/3+2n+4[1-(1/4)^n]/3
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