Assistance with an infinetly nested radical

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fedaykin
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Hello, and thank you for any assistance offered.

I believe the attached nested radical to converge to a value, but I can't find what it is. I've tried the typical recursive function methods to no luck.
 
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  • Infinitely nested radical: square root of 1 + square root of 2 + square root of 4 + square root of 8 + square root of 16 + square root of 32 + square root of (64 + square root of 128), continuing with an ellipsis.
    MSP169819c3481ge0aicd9e00004530bia3aie4d0d3.gif
    3 KB · Views: 642
I believe the attached nested radical to converge to a value
Yes, it converges. To prove it, we compare it to a convergent nested radical.
But the anylitical computation of the limit value is a challenge.
 
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  • Handwritten-style derivation of nested radicals: A equals a nested square root with terms 2 raised to powers of 2, then A equals sqrt(1 + sqrt2 sqrt(1 + ...)), a self-similar sequence equal to (1+sqrt5)/2, giving A = sqrt(1 + (1+sqrt5)/sqrt2), then B = nested radical of powers 2^k, with B < A, and B also finite.
    Nested radical.JPG
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