Using cis (1 Viewer)

[asianese]

We have all seen ...and I have also seen it in the Boardofstudies answers.

My teacher said its not in the syallbus so we should stick to ...but it's obviously a tedious bore to write it all the time.

We are allowed to use in HSC, yes? I don't want to write all the time unless I must.

 

[SpiralFlex]

You must do anything to satisfy your teacher. However in the actual HSC examination, I am confident is accepted.

They used in their sample answers:

http://boardofstudies.nsw.edu.au/hs...df_doc/mathematics-ext2-sample-answers-10.pdf

It's hard to see them marking you wrong while a fair bunch of the state also does it.

 

[asianese]

Yep yep. Thanks

 

[SpiralFlex]

Play the game of the HSC. You need to know exactly what your marking teaching wants you to write for your assessments/trial. Our school got us to write a huge paragraph conclusion after an induction proof or else we would not get the marks.

 

[Shadowdude]

Play the game of the HSC. You need to know exactly what your marking teaching wants you to write for your assessments/trial. Our school got us to write a huge paragraph conclusion after an induction proof or else we would not get the marks.

And then you get into Discrete Maths at UNSW and get David Angell saying how stupid the Board of Studies is for requiring "Assume true for n = k" in induction proofs and also for differing standards on the end statement in induction proofs. I agree with him.

 

[cheese_cheese]

Mathematically the notation is incorrect and frowned upon. For HSC though it is fine to use it.

 

[cutemouse]

cis isn't standard in other countries. The notation e^(i theta) however is... But it's okay for BOS.

 

[Shadowdude]

cis isn't standard in other countries. The notation e^(i theta) however is... But it's okay for BOS.

You'll learn it at uni anyway. Like one of the first things.

 

[cutemouse]

Yeah haha. Btw how do you do it in MATH1081? ie. induction?

 

[Shadowdude]

Pretty much the same.

For example, we must put before anything else: "Theorem: *what we must prove by induction*" and then "Proof (by induction):" before we start.

Then, we have to define variables so it'd be "Let n be an integer." And then we do the basis step as per normal: "The statement for n = 1 is: ... " And then after that, "Thus the statement is true for n = 1. We now assume the statement is true for some particular value of n, and we must prove the case for n+1. That is, we are required to prove: *re-write statement for n+1*"

And then do the induction as per normal, and we can finish off with: "The statement is proved by induction, for all natural numbers", for example.