2012 HSC Extension 2 Mathematics Solutions (1 Viewer)

kman16

Member
Joined
Aug 6, 2012
Messages
45
Gender
Male
HSC
2012
Hey carrot for question 12. d) (ii), once you found the midpoint aren't you then meant to find a cartesian expression for the locus?
Also thanks for the solutions :) Made me realise how simple some of the questions that i couldnt figure out were :(
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
The locus is a fixed point, so there isn't an 'Equation' as you think it is (I presume you mean equation as in a curve).
 

kman16

Member
Joined
Aug 6, 2012
Messages
45
Gender
Male
HSC
2012
The locus is a fixed point, so there isn't an 'Equation' as you think it is (I presume you mean equation as in a curve).
Ahh I see. I wrote x= (u1 + u2)/2 , y=( (z-u1) + (u2-z) ) / 2 and then I eliminated u2 and left an equation in terms of y, x, u1. Do you think I might still get the two marks?
 

Nooblet94

Premium Member
Joined
Feb 5, 2011
Messages
1,044
Gender
Male
HSC
2012
Carrot brah, thought you were coming to girra. totes devo when I walked out and you weren't there :(
 

visipac

New Member
Joined
May 27, 2012
Messages
16
Gender
Male
HSC
2012
Could you please check up on 15)a)ii), isn't it meant to be four identical objects instead of three?
 

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,113
Gender
Male
HSC
2006
Ahh I see. I wrote x= (u1 + u2)/2 , y=( (z-u1) + (u2-z) ) / 2 and then I eliminated u2 and left an equation in terms of y, x, u1. Do you think I might still get the two marks?
I don't think that is correct because u1 and u2 are complex numbers (i.e. x and y still contain an imaginary part within u1, u2 and z)

I personally think that locus question is pretty dodgy or there is some sort of typo because it is obvious by inspection that since B1 and B2 are fixed then clearly their midpoint is fixed.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top