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Math Help - Prove that the relation x_n = 2 + sqrt(x_(n-1) + 1) converges given that x_0>=2.

  1. #1
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    Prove that the relation x_n = 2 + sqrt(x_(n-1) + 1) converges given that x_0>=2.

    I know we can probably make a conjecture, that that if the number is low enough it is a strictly increasing function but converges, and if the number is high enough, it is a strictly decreasing function but converges. How can you prove it without numbers?
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  2. #2
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    Re: Prove that the relation x_n = 2 + sqrt(x_(n-1) + 1) converges given that x_0>=2.

    Hey lm1988.

    Can you get an expansion for this series in terms of n's? (like a power series type expansion)?
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  3. #3
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    Re: Prove that the relation x_n = 2 + sqrt(x_(n-1) + 1) converges given that x_0>=2.

    This problem should not require a power series expansion as it was on a recent test I had to take wherein PS expansion was not among the required material for preparation. We had been taught about convergence and sequences.
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  4. #4
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    Re: Prove that the relation x_n = 2 + sqrt(x_(n-1) + 1) converges given that x_0>=2.

    Well what identities were you given?
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