Mathematics Question Thread

[1937jk]

Hey! Personally, I could never remember stuff like that. So, I would often use my calculator to find zeros (for instance, 0, pi, 2pi and 3pi are all zeros that can be quickly found!) and the use those points as my x-axis. However, it really doesn't matter; choose something that makes sense to you (any regular increment is fine), then use your calculator to figure out what the y coordinate at that point will be.

Okay cool thank you! just to clarify, so you can pretty much use anything relevant to the question as long as their is a consistent increment? E.g To sketch Y =sin (3x) for the domain 0 < x < 2 (they are also less than or equal and vice vera signs i just don't know how to make them come up on here haha) your standard increments wouldn't make sense to use ( pi/2, pi, 3pi/2, 2pi) because that would give you not the correct graph because their is more periods, maybe haha? How would you go about this one?

[Guest8373727727]

Need help with 4 b)

[Guest8373727727]

Question 2

[jakesilove]

Need help with 4 b)

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Hey! First, let's work out the initial domain and range. We know that x has to be greater than -1 (so that we don't have a square root of a negative!) and y will be between -4 and -infinity.

Now, let's consider f(x+2)+4



Great! For this new function, x will have to be greater than -3 (so, we have to shift across 2 units to the left) and y will always be greater than zero (so we shift four units up)

Let me know if I can clarify anything!

[jakesilove]

Question 2
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Hey! All you do here is break the graph up into two sections; one at x<=-3, and one where x>3. For the first section, sketch the straight line y=x+2. Then, ignore the first section completely, and in the second section sketch the other straight line specified. That's it!

[RuiAce]

Question 2
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It will look something like this

[Annie657]

Hi Jake, I am stuck on Question 14 B  Could you please help me? Thankyou 

[jamonwindeyer]

Hi Jake, I am stuck on Question 14 B  Could you please help me? Thankyou 

Hey Annie! Welcome to the forums! I reckon I can help here

The idea is to calculate the odds of losing consecutive draws. The odds of losing \(n\) draws in a row can be given by:



Now we want to be 99% certain that a jackpot prize will have been won. We can consider this as a 1% chance that the Jackpot hasn't been won. So, how many times do we need to draw (aka, the value of \(n\)) for that probability above to reduce to 1% or less?

We can do some trial and error here, at you'll find that after \(228\) draws, the chance of 228 consecutive losses is less than 1%. So, we become 99% certain we have won at least a single jackpot

I hope this makes sense!

[laurenf58]

Could I get some help with the attached questions please?

[jakesilove]

Could I get some help with the attached questions please?

Hey! So, the first question is really only asking you to find where the function is increasing. So, let's differentiate and find where its positive




There are any number of ways that you can solve this equation. I like to do it as follows




So, our two points of interest will be x=9, and x=-1. Let's test points to either side;

For x=0,



which is clearly less than zero. So, the important section isn't between the two points, but rather outside of it! Our answer for where the function is increasing will be



Now, to find where the curve is concave up, we find the double derivative and see where it is positive.



Clearly, this will occur for

[Ellie__]

Hey guys,

So I've got my 1/2 yearlies on Tuesday for this, and well I mostly know my content but it takes me FOREVER to answer a question. Do you have any suggestions on how to be quick and efficient and maybe get 75% of the exam paper complete???


Thaankyou!!!

[RuiAce]

Hey guys,

So I've got my 1/2 yearlies on Tuesday for this, and well I mostly know my content but it takes me FOREVER to answer a question. Do you have any suggestions on how to be quick and efficient and maybe get 75% of the exam paper complete???


Thaankyou!!!

When you are using past papers to study, how are you managing your time?

Simply knowing content will not be enough for mathematics. You need to keep doing past papers so that you can constantly adapt to different types of questions that you may see on the day. And speeding up is another thing that comes with practice, which you need to do a lot of.

When doing the past paper, you should not be overanalysing questions until potentially the last few. With practice comes the ability to generate ideas more quickly. Reading time is the first instance where ideas can be generated. During reading time, you don't have to expect your ideas to actually work, but you should already have a brief idea about what to do. Come writing time, you start putting it to the test. The thing about maths is that if you have an idea that you're confident about, it's usually the right way to go about it. So write it down quickly. And whilst recklessness is common with calculators, there is no need to be too slow with punching in numbers either.

Whilst English was more stressful with continuously writing, maths was (potentially surprisingly) second to it. It's easy to run out of time in maths, so you need to develop quick handwriting abilities for it also.

And as always, follow typical exam guidelines. Get all the marks you can guarantee that you will get first, before moving on to the harder questions that require more thought. Never spend too long on a question and always check the clock if you feel you've just been staring the whole time.

[katnisschung]

hi
needing help with integrating this

thanks!

[RuiAce]

hi
needing help with integrating this

thanks!

As far as 2U goes you don't know how to integrate this.

Was the question given like this or were there other parts to the question?

[katnisschung]

other parts
it was the second part of
differentiate y=x^2e^x

what a legend ruiace! thank gosh i took 2u