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Reply 3940
Original post by Felix Felicis
Haha, yarp xD


How about this? Prove that a rational number + irrational number = irrational


Okays :smile: Can I just use any two numbers and prove using that?
Original post by MathsNerd1
Could anyone give me another question because I'm starting to get back into the mindset for them :smile:


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Prove n!>2nn! > 2^{n} for n4, nZ+n \geq 4, \ n \in \mathbb{Z^{+}}
Original post by Felix Felicis
See that's what the proof is trivial is for but tbh, most people on that thread would decimate these problems within femtoseconds and as AS maths is finished now, it's only A2 candidates left so this thread's died down a bit, so we may as well use it for these lighter problems :ahee:


The only problem is just that the questions in the proof is trivial are out of my reach, and I find these questions a lot easier to answer.:colondollar: I'm actually very glad that you post these questions as I've learned some new techniques.:biggrin:
Original post by Felix Felicis
Prove n!>2nn! > 2^{n} for n4, nZ+n \geq 4, \ n \in \mathbb{Z^{+}}


Well this one looks quite different, I'll see how far I can go with it before getting stuck


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Original post by Felix Felicis
Apologies for the ambiguity, I meant:

irrational + irrational = irrational for all irrational numbers <==== true or false?


Do you just want an answer or a proof as well?

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Original post by tigerz
Okays :smile: Can I just use any two numbers and prove using that?

No, you can't use specific examples :colone:
Original post by justinawe
Do you just want an answer or a proof as well?

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Reply 3947
Original post by Felix Felicis
No, you can't use specific examples :colone:


So I would use x? or w/e
Original post by tigerz
So I would use x? or w/e

Yeah :awesome:
Reply 3949
Original post by Felix Felicis
Yeah :awesome:


LOOL okays time to neglect chem as usual ;O
Original post by Felix Felicis

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Can I just be incredibly lazy and say,

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(edited 10 years ago)
Original post by Felix Felicis
Prove n!>2nn! > 2^{n} for n4, nZ+n \geq 4, \ n \in \mathbb{Z^{+}}


As imagined the inductive step has just baffled me, I don't know how to show the RHS being less than the LHS in a case of K+1 :redface:


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ignore ignore ignore
Original post by justinawe
Can I just be incredibly lazy and say,

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Original post by MathsNerd1
As imagined the inductive step has just baffled me, I don't know how to show the RHS being less than the LHS in a case of K+1 :redface:


There is absolutely no need for induction.
Original post by Felix Felicis
Apologies for the ambiguity, I meant:

irrational + irrational = irrational for all irrational numbers <==== true or false?


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(edited 10 years ago)
Original post by Felix Felicis

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Same difference :dontknow:
Original post by Felix Felicis
Indeed :ahee: Although not that interesting if you cracked it in 2 mins :lol: Just trying to think of random ones off the top of my head :dontknow:

Irrational + Irrational = Irrational <== True or false?


False.

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Original post by Lord of the Flies
There is absolutely no need for induction.


What do you mean?


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Original post by justinawe
Same difference :dontknow:

Well yeah but how much effort do you need to put in to write a random number and then copy and paste it xD

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