VCE Methods Question Thread!

[b^3]

Yeah, in this case k can be negative. I think I might have had just instead of in there originally, and then changed the question, not realising that it changed the answers. I'll add it to the errata thread.

[darklight]

Yeah, in this case k can be negative. I think I might have had just instead of in there originally, and then changed the question, not realising that it changed the answers. I'll add it to the errata thread.

Thanks b^3!

Can anyone help with this question:
If Z has the standard normal distribution and Pr (MODULUS of Z < c) = a where 0<c<3 and 0<a<1, then Pr (Z>-c) = ?

[Phy124]

This is given by the red are below.



(The blue area above)

( hence why we took half of this value)



edit: realised I cropped the image too small and removed part of the image

[Stevensmay]

Snow Red, can I ask how you generated the graphs? I havn't been able to find a good solution yet.

[Phy124]

I just took a random image from google and added to it with word.

However, you can quite easily generate a similar image using desmos.

[Alwin]

How do I graph implicit functions equations on TI-Nspire CAS? (eg. y sin (3x) = x cos (3y))

Sorry, but have just got to rub it in that Casio Classpad can easily implicitly graph (simpler) functions like y²=x+xy. Don't even need to rearrange the formula ^^

I did, however, W|A your question:

THAT'S ONE WEIRD GRAPH

I don't think any cas is going to graph you that LOL

But, on a more serious note, having one cas and not the other will not disadvantage you on the exam. They are tried with both calculators to make sure the questions are solvable in a reasonable amount of time.
There was one time, several years ago according to my teacher, that the classpad couldn't solve a q that the TiNspire could. When the examiners found out (after the exam) they reworked the marks so that q was worth much less marks hence not favouring either cas.

[psyxwar]

Sorry, but have just got to rub it in that Casio Classpad can easily implicitly graph (simpler) functions like y²=x+xy. Don't even need to rearrange the formula ^^

I did, however, W|A your question:

THAT'S ONE WEIRD GRAPH

I don't think any cas is going to graph you that LOL

But, on a more serious note, having one cas and not the other will not disadvantage you on the exam. They are tried with both calculators to make sure the questions are solvable in a reasonable amount of time.
There was one time, several years ago according to my teacher, that the classpad couldn't solve a q that the TiNspire could. When the examiners found out (after the exam) they reworked the marks so that q was worth much less marks hence not favouring either cas.

Nah dw, obviously TI-Nspire is better!

#tinspiremasterrace #classpadplebs

Haha, damn. The textbook where I got the question said it was graphed using computer algebra system. I was hoping my 200$ color screen super cool CAS would be able to do it, but apparently not

[clıppy]

But your $200 color screen super cool CAS can play Pokemon and Doom, can the classpad folks do that? Seriously, can they?

[Eugenet17]

theres a new coloured screen Classpad coming out this year :p

http://edu.casio.com/products/classpad/cp2/

[Zealous]

For an Exam 1 Product Rule question, if it is worth 2 marks, are we expected to factorise by taking out a common factor (simplify)?

[BasicAcid]

For an Exam 1 Product Rule question, if it is worth 2 marks, are we expected to factorise by taking out a common factor (simplify)?

I'm also confused about this, but I usually just multiply everything and if there's negative powers, I turn it into a fraction and leave it at that.
I'm interested in seeing what others think though.

[Phy124]

You shouldn't need to worry as a product rule question will most likely only be worth 1 mark, unless it also asks to find the derivative value at a certain point.

e.g. - 1 mark

- 2 marks

[Jaswinder]

Let X be normally distributed with mean=standard deviation = 27.2

Not let aX be a transformed version of X. If Pr(aX>108. = 0.025 what is the value of a?

I just wanted to know that when X distribution is transformed to aX would be the mean and standard deviation of aX? Thanks

[TrueTears]

Let X be normally distributed with mean=standard deviation = 27.2

Not let aX be a transformed version of X. If Pr(aX>108. = 0.025 what is the value of a?

I just wanted to know that when X distribution is transformed to aX would be the mean and standard deviation of aX? Thanks

For any normal random variable , then any linear transformation of it will still be normal. More precisely, if then .

Or even more generally, if are id normal with mean and variance , then

Try proving both of these results

Method 1: Use the jacobian variable transformation - http://en.wikipedia.org/wiki/Probability_density_function#Dependent_variables_and_change_of_variables

Method 2: Inverse probability transform - http://en.wikipedia.org/wiki/Probability_integral_transform

[Zealous]

For any normal random variable , then any linear transformation of it will still be normal. More precisely, if then .

What if it is a discrete probability distribution? is it the same  (like the probability tables)