MedVision ad

BOS MX2 Trials discussion thread. (2 Viewers)

deswa1

Well-Known Member
Joined
Jul 12, 2011
Messages
2,256
Gender
Male
HSC
2012
Did anybody work out Q16?
Well I definitely didn't- you saw my extensive attempt at Q16 lol. I'll try it sometime soon but I don't think I'll get it...

Why is ln using absolute values?

I have never seen absolute values used with it except on here ?
Yeah you don't need it- I just do it out of habit but its not neccessary
 

deswa1

Well-Known Member
Joined
Jul 12, 2011
Messages
2,256
Gender
Male
HSC
2012
Hey carrot where do you get all these questions their insane :shoot:;)
He made them which is why its extra impressive. I reckon BOS should throw a party for Carrot at the end of the year (srs)
 

Shadowdude

Cult of Personality
Joined
Sep 19, 2009
Messages
12,145
Gender
Male
HSC
2010
This thread is for discussing questions/solutions etc etc.

Here is a copy of the paper: View attachment 26476

I must give sincere thanks to Trebla and seanieg89, who have both greatly helped make the Exam what it is. Their input has been most valuable, and there wouldn't be a BOS Exam without their assistance in checking questions and verifying solutions.

Massive thanks to you both =)
file size: 666KB

IT IS AN OMEN
 

deswa1

Well-Known Member
Joined
Jul 12, 2011
Messages
2,256
Gender
Male
HSC
2012
Ok guys what were your favourite questions in the paper?

Personally, I really liked the prove a+b=c (the tangent question), Q14b (the roots of z^n=1), the whole of Q15 and all those ones about explaining the geometric significance of the result proven. I think I would have like Q16 if I could understand it lol
 

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,384
Gender
Male
HSC
2006
Hey carrot where do you get all these questions their insane :shoot:;)
He made them which is why its extra impressive. I reckon BOS should throw a party for Carrot at the end of the year (srs)
His head **
A lot of them are well known results in higher level mathematics. Also, some of those questions came from me. Namely:
Q8
Q10
Q13b)
Q15a) - though Carrot modified its original form (which had an induction component) and added in part iv)

Notice that those were generally the easier ones :p

Not stealing Carrot's thunder though, most of the good ones were by him.
 

chriss95

Member
Joined
Mar 3, 2011
Messages
63
Gender
Male
HSC
2012
^ was q10 B? Mainly a guess.

If you have a double complex root, does that mean the conjugate is a double as well?
 

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,384
Gender
Male
HSC
2006
^ was q10 B? Mainly a guess.

If you have a double complex root, does that mean the conjugate is a double as well?
Yes, but you also needed to check whether the rest of the roots were real or not
 

deswa1

Well-Known Member
Joined
Jul 12, 2011
Messages
2,256
Gender
Male
HSC
2012
The other roots were not real apparently- I got that one wrong. Lol I got the four unreal roots and I figured it was too much effort for one mark to check the other two :(
 

barbernator

Active Member
Joined
Sep 13, 2010
Messages
1,439
Gender
Male
HSC
2012
@ trebla. Im slowly working my way through Q16. Im doing 16 b) i) 1).

I shuffled the sigma to get it in the form of the inequality, and then applied the absolute value signs, but I am just wondering, why is,



as was stated in a) ?? (as we know that all b(coefficients) are > 0?)
 
Last edited:

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,384
Gender
Male
HSC
2006
You have something like -|x - y| and when x > y, it becomes -(x - y)
 

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,384
Gender
Male
HSC
2006
The other roots were not real apparently- I got that one wrong. Lol I got the four unreal roots and I figured it was too much effort for one mark to check the other two :(
It's not that much effort lol. Quickest way to find two remaining roots is to use the relationship between roots and coefficients.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 2)

Top