VCE Methods Question Thread!

[clıppy]

This question has stumped me. I thought all I had to do was derive C, solve for 0 to find a stationary point and sub it back in but that does not seem to be the case. I think it might have something to do when it mentions 'level of output'. Any help?

[shadows]

I think you just need to step back, and don't blindlessly do the questions following formulas.

You really need to understand the context of the question. Think about it, if the question was relating to flipping a coin (its independent) because the 3rd toss won't affect the 3rd toss. (Theres always a 50/50 chance of getting a heads of tails even if you have previously gotten 5 heads in a row etc.

If it was a question it indicates there isn't a replacement. Then it is not independent.

[lzxnl]

You've misinterpreted the question. C is total cost. The question asks you to not minimise C, but cost per unit. Therefore you need to minimise C/x.

[shadows]

how do i find the intersection of sin(x) and sin(2x)?

[b^3]

Hint

Spoiler

 

[Sanguinne]

i thought double angle formula was used in specialist, not in methods

[shadows]

sin(2x)=2sin(x)cos(x)

is this in study design?

[b^3]

If you're using the Essentials book you might have some exercises with that in it.
Apparently you're only meant to recognise them..
http://www.vcaa.vic.edu.au/Documents/vce/mathematics/mmcasfaqs2011.pdf
http://www.vcaa.vic.edu.au/Documents/vce/mathematics/mathsstd.pdf
Page 130, third dot point

• logarithm laws and exponent laws, recognition of equivalent forms using compound and double
angle formulas for sine, cosine and tangent;

http://www.vcaa.vic.edu.au/Documents/vce/mathematics/mmcasfaqs2011.pdf - Thanks Lazyred.

Are students expected to know and use the compound and double angle formulas
for sine, cosine and tangent?
As noted on page 8 of the June 2010 VCAA Bulletin VCE, VET and VCAL No. 80, students
are not required to memorise compound and double angle formulas for sine, cosine and
tangent for Examination 1. Mathematical Methods (CAS) students will not be required to
apply these to manipulation of expressions involving circular functions by hand. However,
they should be able to recognise them as functional relations involving f(x + y) and f(x – y)
and f(kx) for the circular functions sine, cosine and tangent, and be aware that CAS may
employ these relations in carrying out computations involving circular functions.

EDIT: Fixed.

[clıppy]

Another quick question

A company produces items at a cost price of $2.00 per item. Market research indicates that the likely number of items sold per month will be where p dollars is the selling price of each item. Find the value of p for which the company would expect to maximise its total monthly profit, and the corresponding number of items sold.

I'm completely lost again and any help would be much appreciated

[Lasercookie]

If you're using the Essentials book you might have some exercises with that in it.
I actually previously didn't think it was in the methods study design... but apparently it is...
http://www.vcaa.vic.edu.au/Documents/vce/mathematics/mathsstd.pdf
Page 130, third dot point
EDIT: Note: From http://www.vcaa.vic.edu.au/Pages/vce/studies/mathematics/cas/casindex.aspx
The study design was last updated January 2013

Note the use of "recognition of equivalent forms", I think they mean it in the sense of being able to understand output that the CAS might give, as stated here http://www.vcaa.vic.edu.au/Documents/vce/mathematics/mmcasfaqs2011.pdf (page 2, third question)

[lzxnl]

OK, so we're assuming the company sells everything they make. The cost is 1600/p^2. The revenue is 800/p^2 * p
So profit = 800/p - 1600/p^2
Now just maximise this.

[joey7]

Quick question,

How would you go about finding the intersecting points of the equations

Y=2cos(x) and Y=x-(pi/2)

[Nato]

I just need a little clearing up. (this is 1/2)

so with the addition rule :

i just wanted to know when we don't use .

because some the of the problems i have been doing, i have been able to get the answer by simply , but with others i had to like write down the sample space and manually find , the sub it in.

thanks

[RKTR]

I just need a little clearing up. (this is 1/2)

so with the addition rule :

i just wanted to know when we don't use .

because some the of the problems i have been doing, i have been able to get the answer by simply , but with others i had to like write down the sample space and manually find , the sub it in.

thanks

when they are independent events,u can use  .

when they are dependent, u have to manually find it

[Daenerys Targaryen]

This seems like quite an easy question, but my mind is dead

The probability of Vanessa's car starting on a cold morning is 0.6, while on a normal morning the chance of it starting is 0.9. The probability of any morning being a cold is 0.3. If Vanessa's car starts tomorrow morning, find the probability that the morning is cold.