Maths Methods 3/4 Help Thread 2011

[xZero]

, this only occurs if the graph is y=1, any dilation towards the y axis will not change this function so f(x/5)=1 =>

[tony3272]

, this only occurs if the graph is y=1, any dilation towards the y axis will not change this function so f(x/5)=1 =>

Whoops yeah f(x)=1, not 0 

[b^3]

Thanks guys, I think I get it now, I didn't realise that we had to kinda find the function.

[b^3]

Ok guys another question from past exams, this time vcaa 2009 exam 2. Here is the question, it has a graph that is related.

Its question 1a.

The answer vcaa gave is confusing me. Did they give [9,infinity)? I thought it would be (9,infinity) since the graph is neither decreasing nor increasing at the point 0, found using the derivative. Below attached is what vcaa said. Can anyone help me here, because I'm kinda confused over this?

[xZero]

Strictly decreasing includes the stationary point

[b^3]

Ahh dam! Thats going in my notes then, is there any explanation behind it or are we just meant to know that?, because I don't think I have come across it in the textbook (essential) unless I missed it.

Whooohoooo! 200th post.

[luken93]

Not to go against you or anything xZero, but they say nothing whatsoever about it NOT being what b^3 said, which I imagine would've been a popular answer - I've certainly never heard of that either.

All of the errors are just the usually silly ones, but surely they'd highlight on something that important...

[b^3]

Well considering 72% got it right, they probably did accept it then, thanks guys, but I'm still not giving myself that mark, have to remember it for future because I'f we get an easy exam like chem, they'll be looking for somewhere to take the marks off so. Anyway thanks again.

[xZero]

Not to go against you or anything xZero, but they say nothing whatsoever about it NOT being what b^3 said, which I imagine would've been a popular answer - I've certainly never heard of that either.

All of the errors are just the usually silly ones, but surely they'd highlight on something that important...

I always thought it should be (9,infinity) but VCAA disagrees, its one of those tricks VCAA throws at you so unless if you want to loss a mark because you think VCAA is wrong I would just go with it

Just want to mention that strictly decreasing/increasing includes stationary point but decreasing/increasing doesn't include

[luken93]

Not to go against you or anything xZero, but they say nothing whatsoever about it NOT being what b^3 said, which I imagine would've been a popular answer - I've certainly never heard of that either.

All of the errors are just the usually silly ones, but surely they'd highlight on something that important...

I always thought it should be (9,infinity) but VCAA disagrees, its one of those tricks VCAA throws at you so unless if you want to loss a mark because you think VCAA is wrong I would just go with it

Just want to mention that strictly decreasing/increasing includes stationary point but decreasing/increasing doesn't include

Yeah fair enough, very good to remember though.

[b^3]

Just while you guys are at it, is there any other silly/stupid things that you have come across like this that vcaa has thrown on exams over the last couple of years?

[b^3]

Ok another question guys. Neap 2007 Exam 2 Q1ciii) The exam can be found here -> http://vce.atarnotes.com/forum/index.php/topic,19423.0.html

I cannot work out how the solutions get c=-1. They don't show any working for the question but using the other point of 3pi/2 instead of the pi/2, I still get c=1. Can anyone help?

I would have given you guys a print screen of the page but it's the last question in like a 8 multiple part question (now that I think about it if I tell you guys that I'm less likely to get some help aren't I?)

[gossamer]

Ok another question guys. Neap 2007 Exam 2 Q1ciii) The exam can be found here -> http://vce.atarnotes.com/forum/index.php/topic,19423.0.html

I cannot work out how the solutions get c=-1. They don't show any working for the question but using the other point of 3pi/2 instead of the pi/2, I still get c=1. Can anyone help?

I would have given you guys a print screen of the page but it's the last question in like a 8 multiple part question (now that I think about it if I tell you guys that I'm less likely to get some help aren't I?)

You're using the wrong points. [They are both where g(x)=f(x)]

Take a look at both graphs (and the points where f'(x)=0)), and consider what that final question is asking you.

[b^3]

I hate it when I do stupid things like that, thankyou gossamer.

[kefoo]

Integrate (2-z)(3z + 1),dz
i forgot everything over the holidays lol