Mathematical Induction in the HSC (1 Viewer)

[720YoloSwagScope]

Hey guys, just a quick question before the exam on Monday.
I've heard from some tutors and people that they no longer expect us to have the final statement in MI proofs? I.e. the It is true for n = 1, and proven true for n = k + 1 therefore it is true for all n>=1 or whatever...

Apparently it is still correct by simply writing Therefore true by Mathematical Induction.

Is this true?

 

[Trebla]

Yes. They never expected it in the first place. It's not so much about 'correctness' as the conclusion only explains how the induction process works and is not really part of the underlying proof itself. You just won't get extra marks for writing a conclusion in the HSC.

 

[Speed6]

Tried formatting my post in latex codecogs but the site is down...

Buy anyway, its better to include: n=1, n=k+1 for all positive integers n by MI. Your version is good too, you don't get marks for this conclusion part.

 

[720YoloSwagScope]

Okay thanks for letting me know!
I'm not gonna do it unless I have time lol. Can never remember the correct order it goes.
My teachers deducted marks in trials for the conclusion for one word being wrong..

 

[Speed6]

Okay thanks for letting me know!
I'm not gonna do it unless I have time lol. Can never remember the correct order it goes.
My teachers deducted marks in trials for the conclusion for one word being wrong..

That's ridiculous, if the MI question is worth 3, all those 3 marks usually come from the proving part...Not from spelling/one word being wrong.

 

[720YoloSwagScope]

That's ridiculous, if the MI question is worth 3, all those 3 marks usually come from the proving part...Not from spelling/one word being wrong.

Haha yeah I lost a mark because I started off with something like, "It is true for ..." instead of "If it is true for ... " apparently makes a difference, eh. Idek.

 

[InteGrand]

Just say like 'hence true by mathematical induction' or something.

 

[mrpotatoed]

I just write "by P.O.M.I. true for positive intergers n"

 

[Carrotsticks]

I just write "by P.O.M.I. true for positive intergers n"

I would dock you a mark simply for that spelling of the word "integer".

 

[InteGrand]

I would dock you a mark simply for that spelling of the word "integer".

Lol I was thinking of telling him it's spelt 'integer', but didn't think it'd actually result in loss of marks, so refrained.