Mathematics Question Thread

[jamonwindeyer]

Can I have help with this question too?

Warning: Not 2U content

Hey! First step is to standardise the distribution by defining a new random variable, Y:



This new random variable follows a standard normal distirbution, that is, \(Y\sim\mathcal{N}\left(0,1\right)\). For this we can now use a table of standard normal probabilities. Now what we need corresponds to:



You should be able to use the table to find the answer from there

PS - Is there any reason you stopped posting your questions in this thread? We'd be happy to help you out there, that way we aren't constantly reminding NSW students that your stuff isn't assessable in their course. Would be easier if you posted there from now on if you could

[katnisschung]

can somebody help me integrate this? thanks

[RuiAce]

can somebody help me integrate this? thanks

For extra clarity, the index law \( a^m a^n = a^{m+n}\) was used. This was not necessary, and the same working can be done without it.

______________________________

Side remark: It may have been easier to notice how we have \(\int e^{x+2} dx = e^{x+2}+C \) as an example. Essentially, all we do is replace 2, which is a constant, with -2p, which is also a constant. \(\int e^{x-2p}dx = e^{x-2p}+C\)

[anotherworld2b]

I was advised to post questions here by RuiAce. Im a bit confused where I should post questions

 

Warning: Not 2U content

Hey! First step is to standardise the distribution by defining a new random variable, Y:



This new random variable follows a standard normal distirbution, that is, \(Y\sim\mathcal{N}\left(0,1\right)\). For this we can now use a table of standard normal probabilities. Now what we need corresponds to:



You should be able to use the table to find the answer from there

PS - Is there any reason you stopped posting your questions in this thread? We'd be happy to help you out there, that way we aren't constantly reminding NSW students that your stuff isn't assessable in their course. Would be easier if you posted there from now on if you could

[jamonwindeyer]

I was advised to post questions here by RuiAce. Im a bit confused where I should post questions

Post them in the other section, you are WA after all  - Rui probably asked you to post here so he can see your questions. In honesty, I'm not overly fussed and if you really want to post here you can, but between Rui, Shadow and myself, one of us will spot your questions in the other board.

[winstondarmawan]

Would appreciate help with c)(i).
https://scontent-syd2-1.xx.fbcdn.net/v/t34.0-12/20939088_2364480123777043_876034297_n.jpg?oh=6f825f073179892ac96bbca1fe01300e&oe=599AE038
TIA!

[RuiAce]

Would appreciate help with c)(i).
https://scontent-syd2-1.xx.fbcdn.net/v/t34.0-12/20939088_2364480123777043_876034297_n.jpg?oh=6f825f073179892ac96bbca1fe01300e&oe=599AE038
TIA!

[RuiAce]

Hi...this is only simple yr 11 stuff...but could I have help with this?
Differentiate 2x√​5−x
That square root is meant to continue all the way over the x...
Thanks heaps

You can use brackets to emphasise the √​(5−x)

[gilliesb18]

Hello, can someoneplease help me to differentiate the following question??
1/[x^4 - 3x^3 + 3x]

Thanks...

[Natasha.97]

Hi

I've attached the solution below, hope this helps

[EEEEEEP]

Hello, can someoneplease help me to differentiate the following question??
1/[x^4 - 3x^3 + 3x]

Thanks...

WHen you get a differentiation.. (express it terms of something that you recognise)
- Then differentiate the aspects of it using the rules =)

To differentiate an entire bracket (with x's in it), do the outside then the inside =)

[gilliesb18]

Hi

I've attached the solution below, hope this helps

Thats awesome, makes heaps of sense now thanks!!!

[RuiAce]

Hi

I've attached the solution below, hope this helps

Slight remark - You should have \(\frac{d}{dx} \) in front of your first line. Because the way you wrote it implies that you're saying \( (x^4-3x^3+3x)^{-1}\) actually EQUALS its derivative

[phebsh]

Hey, so I have my math trial on Wednesday and I've been practising past trial papers and I'm constantly failing them even though I'm always practising and asking for help in areas that I'm getting wrong and I just don't know what else to do to improve.
Sorry if this sounds like I'm having a sook, I'm just honestly losing hope... Thanks

[RuiAce]

Hey, so I have my math trial on Wednesday and I've been practising past trial papers and I'm constantly failing them even though I'm always practising and asking for help in areas that I'm getting wrong and I just don't know what else to do to improve.
Sorry if this sounds like I'm having a sook, I'm just honestly losing hope... Thanks

When you say that you're "constantly failing them", in your scenario what does that encompass? Some things to think about:
- Not understanding the question
- Not associating the question with relevant topics
- Simple getting lost in the wording
- Silly mistakes such as misreading numbers and valuse
- Not choosing correct formulae/methods
- Unable to make a choice on formulae/methods
- Sample solutions make no sense
  - Inspiration to use said formula/method confusing
  - Flow of logic confusing
- Spending too long on a question and not moving on
- Grasping probably one half of the content but not understanding the other half
- Difficulty in retaining all the methods

Think about all of these, then clarify your issue further (preferably also with your own areas of concern, not just the list above)