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Calculus/diverging sequence

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Question
Hi, I'm stuck on a question about proving that a sequence does not converge to any limit. the sequence is 2^n. can u help me please??

Answer
Ok, first of all we do agree that : 2^n > n . It's easy to prove.
Now, the definition of a non converging sequence is :
For every N>0 , there exists M>0 such that : for every n>N, we get
|2^n|>M.
Let's apply our Lemma ( 2^n > n ) here :
2^n > n (& n >N) Thus 2^n>N. Therefore if we take M=N we get :
|a(n)|>(N=M) for every n>N.   Q.E.D

Calculus

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Alon Mandes

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Kind of questions I can answer : Limits, Derivatives, Integration, Implicit functions, continuousity, differentiation ,Extremum problems, Lagrange multipliers, Gradients, Surface integrals, Multi variables functions ,Multi variables Integrals,Complex variables ,Complex functions, Curves, Trajectory integrals & Vector analyse,Divergence,Rotor & word problems. Kind of question I can't answer : Economics,Combinatorics,infinite series & convergence ,Statistics & Probabilities .

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