VCE Methods Question Thread!

[TheBamboozler]

Hello everyone. Here's something that I've never been able to get a straight answer on.
I'm wondering if I can put something on the exam that basically says "Using CAS" in place of further working out. My teacher has told me no and my tutor said it should be alright.
Are there any questions where this might be allowed?

[sailinginwater]

Hello everyone. Here's something that I've never been able to get a straight answer on.
I'm wondering if I can put something on the exam that basically says "Using CAS" in place of further working out. My teacher has told me no and my tutor said it should be alright.
Are there any questions where this might be allowed?

I wouldn't risk it unless it's only 1 mark question?

[S_R_K]

Hello everyone. Here's something that I've never been able to get a straight answer on.
I'm wondering if I can put something on the exam that basically says "Using CAS" in place of further working out. My teacher has told me no and my tutor said it should be alright.
Are there any questions where this might be allowed?

"Using CAS" is not accepted mathematical reasoning, so will not be awarded marks.

Generally, in any multiple mark question where you could use CAS to get a final answer, you should write down the expression you have evaluated or equation you have solved or whatever, in order to get the working out marks.

[Lear]

Question: There are 15 blue balls and 5 red balls in a hat. Let p^ be the proportion of red balls in a sample of 5 balls with replacement.
Find Pr(p^=>4/5)

For this would we use the sampling method for p^ or the binomial distribution.
I.e is it
((5c4)(15c1))/(20c5) + ((5c5)(15c0)/(20c5) = 1/204 ~0.0049

or

X ~ (5,0.25)
Pr(X=4) + Pr(X=5) = 0.015625

I've always considered it to be the sampling method where you have to divide the number of ways it can occur by the total number of possible samples. However, in the 2016 VCAA exam 2 Question 3D they simply used the binomial distribution instead of, say, finding the expected number of laptops with a battery life less than 3 hours and then using the above sampling method somehow.

[S_R_K]

Question: There are 15 blue balls and 5 red balls in a hat. Let p^ be the proportion of red balls in a sample of 5 balls with replacement.
Find Pr(p^=>4/5)

For this would we use the sampling method for p^ or the binomial distribution.
I.e is it
((5c4)(15c1))/(20c5) + ((5c5)(15c0)/(20c5) = 1/204 ~0.0049

This method is for sampling without replacement. (ie. 5C4 refers to the number of ways choosing 4 red from 5 red without replacement)

The method using the binomial distribution is the correct one for sampling with replacement.

[sailinginwater]

Say you're doing methods exams from the old study design and you get for instance 55/80 for exam 2, and of the 25 marks you lost, 8 were from the old study design, would it be better to have your score as 55/72 or so in proportion of the full exam so 63/80?
Any opinions?

[Lear]

It really doesn’t matter. Practice exams are for exactly that, practice. I would not worry about the scores you are getting from old study designs. Your main concern should be firstly is this relevant and secondly why did I get it wrong and then how can I avoid this mistake in the future.

[sailinginwater]

If I'm doing practice exams and not understand many of the questions, should I practise questions from my textbook and then after that proceed to doing more practise exams?

[S200]

If I'm doing practice exams and not understand many of the questions, should I practise questions from my textbook and then after that proceed to doing more practise exams?

Yeah. Get the theory and the formulas straight before you apply them.

[S_R_K]

If I'm doing practice exams and not understand many of the questions, should I practise questions from my textbook and then after that proceed to doing more practise exams?

I think it depends on what you are finding difficult. If you are still making mistakes with carrying out basic skills / procedures, then as S200 said you should sort this out before trying to apply them to harder questions.

But if you mostly struggling with interpreting questions and knowing which method to choose, then continue with practice exams. But keep notes on which questions you found difficult to understand; for a variety of questions that all require the same method, look for patterns in the way the questions are asked; after you answer a question and check the solution, think about how you could have come up with that solution strategy by yourself.

[smamsmo22]

Hi, could someone please help me out with these anti differentiation questions? Thanks.

[GMT. -_-]

Hi, could someone please help me out with these anti differentiation questions? Thanks.

You can write a,b and c respectively as
1-(1/x-1)
(3/x+1)-2
2-(1/x+1)
You should be able to integrate them now

[sailinginwater]

y=x*e^(x^2)
1. Could we be asked to sketch the above in exam 1?
2. Could we be asked to find the derivative of the above in exam 1?
3. Could we be asked to find the antiderivative of the above in exam 1?
Thanks 

[Qwerty1234qwerty]

y=x*e^(x^2)
1. Could we be asked to sketch the above in exam 1?
2. Could we be asked to find the derivative of the above in exam 1?
3. Could we be asked to find the antiderivative of the above in exam 1?
Thanks 

1. No (not a function we have learnt to sketch)
2. Yes (product rule and chain rule)
3. No  (unless it is an integration by recognition question where you would use previous parts and the word HENCE would indicate this)

[sailinginwater]

1. No (not a function we have learnt to sketch)
2. Yes (product rule and chain rule)
3. No  (unless it is an integration by recognition question where you would use previous parts and the word HENCE would indicate this)

Thanks   
In binomial and discrete situations for Pr(x>1) the lower bound is 2
Bit in continuous and normal situations for Pr(x>1) the lower bound is 1
Am I correct?