• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

my solutions, all questions (1 Viewer)

failingTheHsc

Member
Joined
Oct 27, 2003
Messages
37
here ya go guys:

Question 1
(a) 0.0302
(b) 3+sec^2 x
(c) 95 degrees
(d) $280
(e) x^3-8x+5
(f) x=10, -4

__________________

Question 2
(a) ex + 2y - 4 + e^2 = 0
(b) i) root(2)
ii) -1
iii) 135
iv) y = -x + 10, C(10, 0)
v) is a proof
vi) 35

__________________

Question 3
(a) i) 18e^x(2e^x-4)^8
ii) x (2 sin x + x cos x)
(b) 89
(c) a graph
(d) i) ln (x^2 + 5) + C
ii) root(3) - 1

_________________

Question 4
(a) i) 55
ii) 64 degreees 28 minutes

(b) i) 1/6
ii) 1/2

c) i) A(1, -3)
ii) 4.5

________________

Question 5
(a) i) proof
ii) (0,0) inflexion and (3, -27) min t.p.
iii) graph
iv) 0 < x < 2

b) i) 63 blocks
ii) 73 rows
iii) 3738 blocks

___________________

Question 6
(a) x = 12
(b) i) alt angles, parallel lines
ii) proof, using supplementary angle and angle sum of triangle
iii) use parallel lines from a single point in ratio

(c) i) C<sub>0</sub> = 5, k = 0.5798
ii) 5.6 years

___________________

Question 7
(a) i) 2 + root(2)
ii) r = 1/(root(2) - 1), |r| < 1. Therefor no limiting sum

b) i) pi/3, 5pi/3
ii) 6ms^-1
iii) is a graph
iv) 9m

___________________

Question 8
(a) y = 2
(b) v = pi {5, 1 (ln y)^2 dy
(c) 11.9
(d) i) proof. do normal thing to see where the lines would intersect and show the discriminant is positive for all values m, so will always have a solution.
ii) m=1 or m= 2/3
iii) y = x - 3 and y = 2/3 x - 4/3

__________________

Question 9
(a) x = 7pi/6, 11pi/6
(b) i) pi/6
ii) pi r^2 / 2
iii) pi r^2 / 3
iv) (pi r^2 - 3 root(3) r^2 ) / 6

(c)I) dL/dt = v - u, v and u are constants, L = (v-u)t. Substitue with the E equation given
ii) v = 3u/2

___________________

Question 10
(a)i) 120000a^2 - Fr - F, r = 1 + 0.06/k
ii) proof.
iii) $2324.47
iv) $498

(b)i) proof. note that XA = 1 - x, PM = 2 - PA, l = XP + PM
ii) just differentiate i) (too much algebra 4 me, i skipped it)
iii) M is closest when l is largest. solve dl/dx = 0, and using the factorisation
x = 1 and some other number involving r's. so i just used 1 ;o)

edit: changed a few answers and got rid of those <sup> things

there ya go. thats wat i did. let me know any agreements disagreements.
 
Last edited:

pri

Member
Joined
Dec 20, 2002
Messages
638
Location
home
Gender
Female
HSC
N/A
fuk u....u seem to have killed it!!!!!!!!!!!!!!!!!
 

Beaky

You can read minds?
Joined
Apr 5, 2003
Messages
1,407
Location
Northen Beaches Pos
Gender
Male
HSC
2003
Originally posted by sepul
heh yeah, you sure the probability anwers are correct tho' ?
Yeah Im going with your first answer 1/6...

Second one 1/2 not too sure bout
 

failingTheHsc

Member
Joined
Oct 27, 2003
Messages
37
Originally posted by Beaky
Yeah Im going with your first answer 1/6...

Second one 1/2 not too sure bout

4 b) ii)
for the probability i did a table of possible outcomes
1 1
1 3 *
1 5
1 7
2 1
2 3 *
2 5
2 7
3 1 *
3 3 *
3 5 *
3 7 *

6 * 1/3 * 1/ 4 = 1/2

wat did u get?
 

SmokedSalmon

Member
Joined
Oct 3, 2003
Messages
900
Location
for me to know and for you to find out
Gender
Undisclosed
HSC
2003
The 1/2 is correct.

1 - (none stop on 3)
1 - (2/3 x 3/4)
1- 1/2
= 1/2

therefore 'failingthehsc' is correct :)

Comparing my answers to yours (of what I can remember) I seem to have everything similar or the same. A few are different but couldn't be bothered to post up.
 

Beaky

You can read minds?
Joined
Apr 5, 2003
Messages
1,407
Location
Northen Beaches Pos
Gender
Male
HSC
2003
bahhh your right :D

I can see

wat i did was P(3,x) P(x,3)
which is like 1/3 x 1/4 + 1/3 x 1/4

WTF was i thinking!!!

lol your gonna cane it both of u guys... prob 110+ good job... :D
 

PoLaRbEaR

The Bear
Joined
Apr 13, 2003
Messages
253
Location
Sydney
Gender
Male
HSC
2003
Question 4
(a) i) 55
ii) 64 degreees 28 minutes
i) It says the bearing is 325 degrees...so angle PQR is:
360-325 = 35 degrees
ii)You should get at most 2 out of 3 marks because of your first one being wrong
 

Winston

Active Member
Joined
Aug 30, 2002
Messages
6,128
Gender
Undisclosed
HSC
2003
Originally posted by PoLaRbEaR
i) It says the bearing is 325 degrees...so angle PQR is:
360-325 = 35 degrees
ii)You should get at most 2 out of 3 marks because of your first one being wrong
No it's not 360 dude

the whole thing is 325

so you minus the 3 quadrants


325-270 = 55
 

iambored

dum-di-dum
Joined
Apr 27, 2003
Messages
10,862
Location
here
Gender
Undisclosed
HSC
2003
Originally posted by failingTheHsc
question 8
(b) v = pi {<sup>5</sup><sub>1</sub> (ln y)<sup>2</sup> dy
( [/B]
is that wrong? because u can't integrate a log

but come to think of it i found the area!! argh!
 

Winston

Active Member
Joined
Aug 30, 2002
Messages
6,128
Gender
Undisclosed
HSC
2003
Originally posted by iambored
is that wrong? because u can't integrate a log

but come to think of it i found the area!! argh!
take a look at my solution on the the solutions thread



meh don't worry about the logic of not being able to integrate a log, in theory it can be done, just not at our level of maths, but they didn't ask us for it anyways. They just wanted the equation.
 

SoCal

Hollywood
Joined
Jul 5, 2003
Messages
3,913
Location
California
Gender
Male
HSC
2003
I must have made at least 15 marks worth of stupid mistakes:mad: and don't you just hate it when you cross out the right answer and put a different answer in:mad:.

How are you supposed to answer Question 9 (a):confused:?
 

spark

Member
Joined
Dec 24, 2002
Messages
208
I just marked mine against this and I probably got 65% more or less. How fucking fantastic!
 

Sah

New Member
Joined
Oct 27, 2003
Messages
5
integration of ln x is
xlnx - x :) it works but we didnt have to do it and i dont know integration of (ln x) square

umm for question 10b last one i got 2 answers x=1 and x=r and i thought x=r was the correct one when i subbed it, maybe i chose wrong one cause i was presed for time.
 

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

Top