#Turning recursive sequence into an explicit sequence

28 messages · Page 1 of 1 (latest)

dull zephyrBOT
orchid scrollBOT
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Bunjeet

flat merlin
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<@&286206848099549185>

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<@&286206848099549185>

flat merlin
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<@&286206848099549185>

night jacinth
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Can you share the actual question? You should always share the original question, by the way.

flat merlin
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@night jacinth this is basically the whole question, apart from where the question says to prove the sequence is increasing

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i understand to do that i need to do induction

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but from what i understand i need to turn this recursive formula into an explicit one in order to be able to do that induction

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that is the part i am stuck on

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<@&286206848099549185>

quaint axle
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What you think is irrelevant might not be irrelevant to us

quaint axle
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You can do that with induction

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Prove that $x_{n+1}>x_n \Rightarrow x_{n+2}>x_{n+1}$

orchid scrollBOT
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FirstNameLastName

flat merlin
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@quaint axle Sorry i dont have the exact question written out properly, just in hand notes, but yes i just have to show that the sequence is increasing and give an upper bound. So, with what you have said here, if i prove x_x+2>xn+1 does it then imply x_n+1 >xn or no?

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how would i prove x_n+1>x_n if i dont know what x_n is

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thanks for helping aswell

lethal totem
# flat merlin <@678340429175062552> Sorry i dont have the exact question written out properly,...

If you gonna do this by Induction you don't need to know x_n.

Just begin by showing that for the smallest n = 1 the inequality is true.

Then after you found at least one n ∈ ℕ that makes xₙ₊₁ > xₙ true.
This will be your precondition for your Induction. (1).

∃ n ∈ ℕ : xₙ₊₁ > xₙ (1)

Now the second step is as already mentioned above to show it for n -> n+1.

In other terms:

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Prove $x_{n+2}>x_{n+1}$

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You need to transform the inequality in such a way where you can use your Induction assumption (1). By doing that you completed the proof then.

orchid scrollBOT
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adoniszgks

flat merlin
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thank you

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!solved

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.solve

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.solved