VCE Methods Question Thread!

[~T]

As for the second question... I don't think a system of 3 equations with 3 variables can have multiple solutions unless it has infinite solutions. They represent planes in three dimensions, so three planes cannot intersect at more than one point unless it is on a line or a plane, yes? I think so... 

So, do a similar thing as with the previous question. Find when the determinant is equal to zero, if there are multiple cases then solve each until you find there are infinite solutions. Otherwise just solve the one. This will give you the answer in terms of another parameter. Which I guess is what the question is asking for.

[~T]

Now for my quick query, is it acceptable to leave a constant or a factor of some form out in front of a matrix? Such as when you are finding the inverse and you divide everything by the determinant, are VCAA totally cool with you leaving it out the front?

[Limista]

Now for my quick query, is it acceptable to leave a constant or a factor of some form out in front of a matrix? Such as when you are finding the inverse and you divide everything by the determinant, are VCAA totally cool with you leaving it out the front?

I don't really want to give an answer without fully understanding what you mean. Could you provide an example?

[Stick]

I think what he means is not multiplying the fraction in front of a matrix into each entry after finding the inverse of a matrix.

[BubbleWrapMan]

As for the second question... I don't think a system of 3 equations with 3 variables can have multiple solutions unless it has infinite solutions. They represent planes in three dimensions, so three planes cannot intersect at more than one point unless it is on a line or a plane, yes? I think so... 

So, do a similar thing as with the previous question. Find when the determinant is equal to zero, if there are multiple cases then solve each until you find there are infinite solutions. Otherwise just solve the one. This will give you the answer in terms of another parameter. Which I guess is what the question is asking for.

This is correct, systems of linear equations can't have a finite number of solutions that is greater than one, so if there is more than one solution there are infinitely many solutions.

Now for my quick query, is it acceptable to leave a constant or a factor of some form out in front of a matrix? Such as when you are finding the inverse and you divide everything by the determinant, are VCAA totally cool with you leaving it out the front?

That's fine, it usually looks better that way, but for the record matrices in methods usually aren't even that complicated.

[abcdqdxD]

Is it necessary to do EVERY single question in the textbook? My teacher seems to think so..

Would it be a good idea to do some questions from my current textbook, a few from another textbook, then move onto checkpoints questions relating to the AOS?

[pi]

Is it necessary to do EVERY single question in the textbook? My teacher seems to think so..

I'll be honest, I did not do questions from the textbook after the chapter on log graphs in MQ (chapter 4 or something?). Spent the time doing prac SACs and listening to my teacher instead

I do regret not doing questions from the prob section of my textbook though (esp. conditional prob). So watch out for that.

[Stick]

Consider the point (4, -3) on the graph y=f(x). What is the co-ordinate of the image under the transformation f(2x-3)?

I think I got this right, I'm just seeking confirmation.

[brightsky]

(7/2,-3)

[Stick]

Thanks. I just wanted to confirm that we can factorise that 2x-3 to 2(x-1.5). I'm starting to get the hang of your recognition method now.

[darklight]

wait, can you explain how you two got that?



Wait, no problem - I think I've got it.

[chisel]

Thanks. I just wanted to confirm that we can factorise that 2x-3 to 2(x-1.5). I'm starting to get the hang of your recognition method now.

sorry to be nosy but how did you get that answer?

[pi]

sorry to be nosy but how did you get that answer?

Consider the point (4, -3) on the graph y=f(x). What is the co-ordinate of the image under the transformation f(2x-3)

So, f(x) -> f(2(x-3/2))
Apply dilation first, factor of 1/2 from y-axis. Then apply translation of 3/2 in positive direction of x-axis.
Hence (4, -3) -> (4/2, -3) -> (7/2, -3)

[chisel]

Consider the point (4, -3) on the graph y=f(x). What is the co-ordinate of the image under the transformation f(2x-3)

So, f(x) -> f(2(x-3/2))
Apply dilation first, factor of 1/2 from y-axis. Then apply translation of 3/2 in positive direction of x-axis.
Hence (4, -3) -> (4/2, -3) -> (7/2, -3)

nice explanation, cheers mate 

[chisel]

While i'm here i have a couple of pretty basic questions:

firstly, what are two applications of the process of "completing the square" for a quadratic expression?

secondly, For which values of 'm' does the equation mx^2 - 2mx +3 = 0 have exactly one solution?

cheers guys