# IB HL Paper 2 2012 TZ2 - as soon as we're allowed to discuss it...

Discussion in 'Mathematics' started by beedge, May 5, 2012.

1. ### beedgeNew commenter

I'd like someone to explain how to do Q7a without guessing the value of "a". I'm either missing something obvious, or this is a very unfair question. Surely you're not expected to integrate that function??

2. ### beedgeNew commenter

I'd like someone to explain how to do Q7a without guessing the value of "a". I'm either missing something obvious, or this is a very unfair question. Surely you're not expected to integrate that function??

3. ### KarvolOccasional commenter

Q7 is simple question on sketching the reciprocal of a function. A is (-1,4) therefore giving the image of A as (-1,0.25).
Are you mistaking with question 8?
On question 8, you implicitly differentiate x^3y = asin nx and it fairly easily gives the required second order differential.
However there is no part a on Q8.
Is it TZ1? I have just had a look at the TZ1 question and there isn't anything there either.

4. ### KarvolOccasional commenter

OOOPSSSS!!!!
BIG apology. I was looking at Paper 1!

5. ### beedgeNew commenter

no problem - have you worked out how to do it yet?

6. ### KarvolOccasional commenter

We don't have Paper 2 yet.

7. ### ian60New commenter

The pdf given is certainly not a standard integral, and I think it reasonable to expect an HL student to recognise a non-standard integral as such, and then to realise that this is a calculator exam.
I took 4 attempts at guessing the value of 'a' before I got the area under the graph to be 1 to 4 sf. using the TI-84
It wasn't very time consuming, but was it fair? I think I have seen far nastier questions in the past, but I imagine it would have tripped up most of my students who really haven't enjoyed anything off the straight and narrow.

8. ### beedgeNew commenter

So I'm glad it wasn't just me that had to do a bit of "trial and improvement". It just seems slightly unsatisfactory that it's not possible to calculate an exact solution (within the confines of the course); normally of course the PDF is fairly straight forward to integrate, so I'm sure this question will have thrown my students too.

9. ### ian60New commenter

One of my students told me that she 'made up' a value for 'a' for the purposes of part b), I am hoping she will have been awarded some (M) marks.
(far too many letters floating around there)

10. ### KarvolOccasional commenter

For Paper 2 it would be an error to presume such a situation. Paper 2 is designed so that the calculator is required. That should be the first option for students. Analytical solutions are for Paper 1.

11. ### bbibblerNew commenter

There seem to more and more of this type of question in HL papers recently.

Am I the only one that is getting concerned by the close relationship that
has grown between IB and Texas/Casio?

They seem to forcing all students to become experts in using a GDC. Are GDCs
used anywhere else, or is it just in Maths Education.

Once student have a Diploma, they would chuck the GDC in the back of a
drawer and never use it again. There are programs on PCs that do all of the functions
of a GDC, so why not scrap the GDC and offer A COURSE THAT ALLOWS laptops
FOR ALL CALCULATIONS.(they could call it computing or colouring in.

Then we could have our beautiful subject back.

12. ### KarvolOccasional commenter

It depends how you look upon the subject.
Paper 1 is for theoretical or analytical mathematics.
Paper 2 is for using technology in mathematics.
The exploration is for looking at mathematics in the wider community.
In my opinion, Paper 2 should enable students to use CAS calculators and the paper should be more focused on the application of knowledge, rather than questions with dodgy numbers.

13. ### bbibblerNew commenter

I would like to see paper 2 contain questions that can be solved without using a GDC.

Having 1 paper where you cannot use a GDC and one where you can use a GDC is a good idea.

BUT

Having questions that can only be solved by using the advanced features on a GDC is a mockery of what HL maths should be about.

I agree that the Exploration is a great leap forward from our present IAs, but I wonder if coursework has any place in Maths.

You say that they should allow CAS GDCs, I say that they should go the whole way and have 2 courses. One HL course with only basic Cals and one course that allows all types of electronic devices, including Pcs and Laptops.

GDCs are hardly used outside the IB, the real world would be using a mainstream medium. PDAs, Tablets et all would be much better that the blind ally of a GDC. Why are we teaching Kids to use a GDC when they will only use it for 2 years and then chuck it?

14. ### KarvolOccasional commenter

Why? What is so special about HL? It is, in reality, not that much more difficult than SL. Using a calculator tests knowledge of techniques on a calculator. If a student wishes to do well at HL, they need to be both analytically able and technologically able. Just one or the other is not going to cut it. If anything, it raises the threshold higher as one needs to be an all-rounder.
The medium is not the message. Using the GDC teaches the students techniques that are applicable to other software packages that the students will be using in their later careers.
The Nspire, for instance, has a spreadsheet, graphing software and statistical packages. It is appropriate for the needs of the student at that level. Paying 100 odd quid for something that is going to be used for two years in a number of subjects is not a big deal.
I think to expect the students to only use those things that they are going to be using in their future careers is rather missing the point of school. It is not a training ground for future employment. It is a method of allowing the students to learn the skills to teach themselves the skills that they will need in the future, as and when they need them.
I also feel that this idealised world that some maths teachers live in, that students in HL should be using purely analytical methods, is in itself somewhat mistaken. The maths that we do prior to university level is rather trivial. There is nothing that can be taught at school that will not be covered within a few months at a decent university, so why waste time in thinking that it needs to be relevant? How many students who opt for HL end up at university to study mathematics?

15. ### ian60New commenter

I think the P2 does serve a very useful purpose, and I agree with all Karvol has said.
About 6 years ago I started an MSc Applied Stats course. There was a fair whack of theory, but a heck of a lot of it was all about getting the hang of the statistical packages that were commonly used (SPSS or Minitab), and using it in a meaningful manner.
Where is the harm in allowing students to explore mathematics using technology, it has certainly enhanced my understanding of several topics.
And if they can learn using technology, why not assess this learning using the same medium.
I believe there are some parts of the US where you are allowed to us CAS calculators or Lap tops, that moves the goal posts in terms of learning and assessment. My mind boggles.
Having said all this, I'd still want a student to recognise when to use the product rule, and when to use the quotient rule...etc