数列满足2Sn=A(n+1) -2^(n+1)+1” 如何证明{an+2的n次方}为等比数列

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数列满足2Sn=A(n+1) -2^(n+1)+1” 如何证明{an+2的n次方}为等比数列

数列满足2Sn=A(n+1) -2^(n+1)+1” 如何证明{an+2的n次方}为等比数列
数列满足2Sn=A(n+1) -2^(n+1)+1” 如何证明{an+2的n次方}为等比数列

数列满足2Sn=A(n+1) -2^(n+1)+1” 如何证明{an+2的n次方}为等比数列
2Sn = a(n+1) -2^(n+1) +1
an = Sn -S(n-1)
2an =a(n+1) -2^(n+1) - [an -2^n]
a(n+1) = 3an + 2^n
a(n+1) + 2^(n+1) = 3[ an + 2^n ]
=>{an + 2^n} 是等比数列,q=3

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