May 26, 2020, 11:29:57 pm

### AuthorTopic: Sample solutions to QCAA's sample papers  (Read 924 times)

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#### RuiAce

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##### Sample solutions to QCAA's sample papers
« on: September 15, 2019, 10:08:38 pm »
+7

To get a better feel for how your exams will be administered, I will release solutions to the sample papers QCAA have recently released. For Maths Methods, the papers can be accessed here.

Note that these solutions serve only as samples and are not endorsed by any other party.

Paper 1 (Technology-free)

Multiple choice
Q4 updated as per comments below.

Questions 11-13

Questions 14-16

Questions 17-18

Paper 2 (Technology-active)

Multiple choice Questions 1-5

Multiple choice Questions 6-10

Questions 11-14

Questions 15-17

Questions 18-19

Question 20

« Last Edit: April 23, 2020, 11:22:10 am by RuiAce »

#### Specialist_maths

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##### Re: Sample solutions to QCAA's sample papers
« Reply #1 on: October 19, 2019, 11:21:28 pm »
+4
Re: Question 4

The Queensland syllabus refers to phi as the altitude angle. In Question 4, the angle subtended by the altitude of OA above the xy-plane is AOB (as per the QCAA solutions).

This matches the 'everyday' use of the word altitude.
https://en.wikipedia.org/wiki/Azimuth#/media/File:Azimuth-Altitude_schematic.svg
The newly published textbooks have also gone with this definition (see attached image).

However: This does not mach the traditional mathematical convention of using phi for the polar angle (AOC).

I agree Rui, it's frustrating to have different conventions (eg: the ISO uses phi for azimuth).
Teacher of 2020 Seniors: Specialist Mathematics + Mathematical Methods
QCAA Assessor

#### RuiAce

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##### Re: Sample solutions to QCAA's sample papers
« Reply #2 on: October 20, 2019, 12:34:49 pm »
+1
-snip
Appreciate the input heaps!

Yeah, it irks me a lot because it's not said traditional mathematical convention. I understand it for General maths and latitudes of the Earth, but I really would've preferred the traditional for Spesh.

#### RuiAce

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##### Re: Sample solutions to QCAA's sample papers
« Reply #3 on: January 05, 2020, 11:57:17 am »
+4
Paper 2 solutions are done for specialist as well now. (Methods solutions were updated yesterday.)

There is one thing very important to mention here. As of 4 Jan, Question 3 of the paper is technically nonsense. The point $(1,\pi)$ certainly does not lie on the curve $2e^x - 3y^2 =1$ to begin with!

For this problem, the correct answer should technically be "the implicit derivative does not exist" at that point. It turns out that when you plug the point into the formula, you do get a valid answer. But that's not justified, simply because the implicit derivative is only defined for points actually on the curve.

#### qcexaminer

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##### Re: Sample solutions to QCAA's sample papers
« Reply #4 on: April 15, 2020, 07:57:48 pm »
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Nice work sharing these solutions, despite some pretty low grade sample questions (eg Q3, so bad ) from QCAA. Pretty sure you might want to check Spec Q6 as k=3, (C). Dot product of (2, k, 4) should be with normal (1, -2, 1), not the vector in plane (3, 4, 5).

#### RuiAce

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##### Re: Sample solutions to QCAA's sample papers
« Reply #5 on: April 23, 2020, 12:23:53 pm »
+2
Nice work sharing these solutions, despite some pretty low grade sample questions (eg Q3, so bad ) from QCAA. Pretty sure you might want to check Spec Q6 as k=3, (C). Dot product of (2, k, 4) should be with normal (1, -2, 1), not the vector in plane (3, 4, 5).
Yep thanks! I must've mixed up my points when I was doing that question then.

Q3... but looks like it's fixed now at least! It seems to say $2e^x -3y^2+3\pi^2 =2e$ now.