(an)^2+(a(n+1)+2)an +2a(n+1) +1 =0
(an +1)^2 + a(n+1).(an + 2) =0
a(n+1) = -(an + 1)^2 /( an+2 )
Prove by induction ,
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数列与数学归纳法
(an)^2+(a(n+1)+2)an +2a(n+1) +1 =0
(an +1)^2 + a(n+1).(an + 2) =0
a(n+1) = -(an + 1)^2 /( an+2 )
Prove by induction ,
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