VCE Methods Question Thread!

[MB_]

If \(sin(x)=-\frac{2}{15}\) and \(π≤x≤2π\) then \(sin(\frac{3π}{2}-x)\) could equal ... not really sure how to go about solving this question. Thanks in advance

[qwertyu1234567]

Sorry to be annoying, but I'm stuck again   
Question is attached

[wyzard]

If \(sin(x)=-\frac{2}{15}\) and \(π≤x≤2π\) then \(sin(\frac{3π}{2}-x)\) could equal ... not really sure how to go about solving this question. Thanks in advance

Think in terms of quadrants. Which quadrant does x belong to originally? Then which quadrant does 3π/2-x belong to?

Also the following identiy might be useful:

[wyzard]

Sorry to be annoying, but I'm stuck again   
Question is attached

For the first part, it is another binomial distribution with p = 0.03 and n = 4, since the manager picks 4 at random. Then find the probability that more than or equal to one is selected.

For second is the opposite of the forst, this time you know the probability, but you'll have to find n such that the chance is at least 0.5.

[tennis1]

Hey, does anyone know how to solve this??

integral from 5 to 4( 2/2x-1) dx=loge(b)

^It's the VCE 2014 Q2 paper 1. I don't really understand the working in the answers :/
http://www.vcaa.vic.edu.au/Documents/exams/mathematics/2014/2014mmcas1-w.pdf

[MB_]

Think in terms of quadrants. Which quadrant does x belong to originally? Then which quadrant does 3π/2-x belong to?

Also the following identiy might be useful:

I don't really know how that helps me, would you be able to explain?

[bedigursimran]

Hey guys. Do you know how to do VCAA 2010 Exam 2 Question 4 f? I have no clue where to start and the assessment report makes no sense. Thanks!

[wyzard]

I don't really know how that helps me, would you be able to explain?

As x is originally could be in the 3rd or 4th (the one at the bottom), taking 3π/2 subtracted by x will result in it either being in the 1st or 4th quadrant, but the angle with the x-axis is changed from x to π/2 - x. You'll need to draw the diagram and angles to see this.

Actually I just thought of a much neater way to work this out. First take note that:


Now make use of symmetry as:


We can see that:


Since we know what sin(x) is, we can then find out what cos(x) is.

[esthertham58]

Can someone help me with Q 107?

The answer says to use the inverse of the function but I don't really get the solutions. Thanks!

[JellyBeanz]

Can someone help me with Q 107?

The answer says to use the inverse of the function but I don't really get the solutions. Thanks!

The reason why you need to use the inverse is because you are finding the region bounded by the y  - axis and hence have to integrate with respect to y. Therefore you find the inverse and integrate from 0 to 3

[nadiaaa]

In the simplest way possible can someone explain this to me?
I dont understand it at all...
(VCAA q.20 2014 exam 2)

[JellyBeanz]

In the simplest way possible can someone explain this to me?
I dont understand it at all...
(VCAA q.20 2014 exam 2)

Well the average value is given by Area under h(x) / interval of x-values. (Standard average value formula)

Therefore find the area of the triangle 2*(1/2(4+10)*5)

and divide by 10 (11-1 is the interval)

answer should be 7.

[MightyBeh]

In the simplest way possible can someone explain this to me?
I dont understand it at all...
(VCAA q.20 2014 exam 2)

Jellybeanz beat me to posting but I'm gonna posat my solution anyway

[Gromekk]

Hey, just finished the mav 2016 exam. Just got a question about the very last question, attached is the question and worked solution. How do they get to the step highlighted?

[exit]

Hey, just finished the mav 2016 exam. Just got a question about the very last question, attached is the question and worked solution. How do they get to the step highlighted?

-1= the top log from the previous as o.1=1/10=10^-1 (and move the -1 to the front of log)

the bottom bit they're the separating the log.