VCE Methods Question Thread!

[Reus]

I predict questions that will confuse everybody.

Gosh you guys are comedians!!!!!

Have you seen this thread? Can't remember how much exam 1 was talked about but may be good to look through

Methods Exams 2014: Predictions

Thanks mate.

[vcestudent123]

Gosh you guys are comedians!!!!! Thanks mate.

It's all I have left
but there may be a Linear Approximation question..
It has been a while since they had it on the exams and it may catch a few people off guard.

[Jason12]

confused with parts aii and b. In b the report says to find the gradient they do (f(-6) - 0)/(-6-0) but shouldn't it be f(-6) - f(0) which would change the answer?

[Kaleidoscope]

Perhaps addition of ordinates will appear on either exam?

[IndefatigableLover]

Perhaps addition of ordinates will appear on either exam?

Considering how hard it is to actually mark addition of ordinates, I'd doubt it'd be on the exam and if it is, then it'd have to be a pretty easy question imo (since it just takes too much time to mark for that question)... that's what I think anyway

[keltingmeith]

Perhaps addition of ordinates will appear on either exam?

Ehhh - VCAA care more about the actual function than sketching it.

Plus, addition of ordinates on exam 2 would be pointless because you have a calculator to graph it for you. Exam 1, though, it could come up.

[soNasty]

mav 2014 exam 1 had addition of ordinates
it was easy tho
anyway yeah i think theres gonna be something big about related rates, or one of those application questions with integrals... what are they called... kinematics or something

[BLACKCATT]

Is it possible to get a question that will "freeze" your cas? For MAV 2013 exam 2, one of the questions i had to wait a long while for the cas to solve ._.

[silverpixeli]

Is it possible to get a question that will "freeze" your cas? For MAV 2013 exam 2, one of the questions i had to wait a long while for the cas to solve ._.

yeah large matrices, very dense graphs and anythign else that's really computationally intensive can take ages and you want to avoid that in exams. While it's possible to come up with such commands to try and see how long it takes, VCAA isn't going to put anything in the exam which is meant to be solved by CAS but takes more than a second or so to compute.

[Damo23]

Well hey I need a hand solving the equation 2sinx+1=b, where b is positive real number and has 1 solution between [0,2pi], so whats the value of b?

Sorry to annoy u guys, I couldn't find a unit 1/2 thread 

[M_BONG]

Hey guys,

for a general solution answer would I lose marks if I am not specific which what values the integer can be.

Eg.
I need t equals or more than 6


But I leave it as x = 2 n + 6    , n element of Z?

As in, would I lose marks for not saying n is an element of Z + including 0?

Or do they only expect n element of Z when doing general solutions? Sorry if you the question is a bit confusing!

[silverpixeli]

Hey guys,

for a general solution answer would I lose marks if I am not specific which what values the integer can be.

Eg.
I need t equals or more than 6


But I leave it as x = 2 n + 6    , n element of Z?

As in, would I lose marks for not saying n is an element of Z + including 0?

Or do they only expect n element of Z when doing general solutions? Sorry if you the question is a bit confusing!

you probably need to say it though I've never been asked to place an extra restriction on Z, you could say or or equivalent

[IndefatigableLover]

Well hey I need a hand solving the equation 2sinx+1=b, where b is positive real number and has 1 solution between [0,2pi], so whats the value of b?

Sorry to annoy u guys, I couldn't find a unit 1/2 thread 

If it's going to have 1 solution between [0, 2pi] then your 'x'-values' will either be pi/2 or 3pi/2 which you will sub in to find when 'b' is a positive real number (that is b=3 which is your final answer).

I guess to picture this is when you have a unit circle and you go around the circle at x=0, pi/2, pi , 3pi/2 and 2pi, what do they equal when you substitute the 'x-value' in sin(x)? You'll find that at x=0 and x=2pi equal the same thing (hence eliminating those 'x-values as they both equal zero whilst the others give you values of 1 and -1).
Using your exact values won't work since you only want 1 solution between [0, 2pi] as your exact values will give you 2 solutions.. like sin(pi/3) is the same as sin(2pi/3) yet they equal the same value so it'll give you two solutions leaving you with only -1 and 1 as values which you can sub in... hope that makes sense!

[silverpixeli]

Oh ok cheers.

My concern is when it becomes complicated; such as t > equals 5

x = -2n +  1 and -6 n + 1

(ie. when you have two sets of general solutions for cosine and sine - yes I do it that way..)


But let's hope VCAA doesn't make it so complex....

I see what you mean, but yeah I've never seen them mix general solutions AND inequalities like that. Just keep your cool and write down the numbers you mean, even if it's like {5,6,7,...} or something they'll get the message. You're not being assessed on set notation you're being assessed on trig

[Reus]

Could someone please do b? Thanks.