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Shot gun question ONE:

a) 2cospi/5 = 1.62 to 3 s.f.

b) Factorise 3x^2 + x - 2 = (3x - 2) (x + 1)

c) Simplify 2/n - 1/(n+1) = (n+2)/(n^2 + n)

d) |4x - 3| = 7 x= 5/2 and -1

e) (rt3 - 1)(2rt3 + 5) = 1 + 3rt3

f) Sum of 1st 21 terms of 3+7+11... = 903
 
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emo-kid-91

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(i think i got these right. lol!)

question two:

a. i. 18x(x^2+3)^8

ii. 2xlnx + x

iii. xcox + 4cox - sinx / (x+4)^2

b. M = (2, 6)
x + 2y - 14 = 0

c. i. ln(x+5) + C
ii. 1/3
 
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Question FOUR:

a) < YRX = < XRQ (XR bisects <PRQ, given)
< XRQ = < RXY (alternate angels, XY||QR)
.:. Triangle XYR is isosceles (2 equal angles in triangle)

b) i) 215 mm
ii) 12 times

c) i) (0, 3)
ii) (0, 5)
iii) Yeah just show the points :p Looks like a normal parabola hoisted 3 up.
iv) 10 2/3 units
 

-MikeY-

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c) Simplify 2/n - 1/(n+1) = (n+1)/(n^2 + n)



Sorry but you lost a mark here. its (n+2)/(n^2+n) - 2 x n+1 = 2n+2
 
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hahaha yeah mike you're right (pretty sure i got it right in the test :p this is me doing them post-test)
 

emo-kid-91

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karnage said:
13 times?
this has already been argued. when working it out without any formulas, it comes out as 12. 50, the first value, is not a zooming in value and is therefore not part of the gp.
 

farkmedead

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-MikeY- said:
c) Simplify 2/n - 1/(n+1) = (n+1)/(n^2 + n)



Sorry but you lost a mark here. its (n+2)/(n^2+n) - 2 x n+1 = 2n+2
i don't get what you're saying but i remember my answer had i think (n+2)/(n^2+n)
i THINK.

also, does anyone have the test? i.e. the questions or remember them LOL
 

Rampager

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c) Simplify 2/n - 1/(n+1) = (n+1)/(n^2 + n)
Say what?

2(n+1) - n
------------
n(n+1)


2n + 2 - n
------------
n(n+1)


= n + 2
---------
n(n+1)


full marks
I guess not anymore...


Question 4 b)
50 x 1.2 = 60 (first application)
60 x 1.2 = 72 (second application)
72 x 1.2 = 86.4 (third)
86.4 x 1.2 = 103.68 (fourth)
103.68 x 1.2 = 124.416 (fifth)
124.416 x 1.2 = 149.2992 (sixth)
149.2992 x 1.2 = 179.159 (seventh)
179.159 x 1.2 = 214.49 (eighth)

continuing on...

214.49 x 1.2 = 257 (ninth)
257 x 1.2 = 308.86 (tenth)
308 x 1.2 = 370 (eleventh)
370 x 1.2 = 444 (twelfth)


before anyone argues.
 
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syriangabsta

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Question 3:

(a)

(i) y2-y1/x2-x1 = 2. (for line BC)
y=2x -1, therefore m=2 (for line AD) therefore, parralell.

(ii) y-coordinate is 5, since its paralell to x-axis and its along with the point C.
x-coordinate.... 2x - y - 1 = 0. when y=5, 2x-5-1 = 0. x=3. Dis at (3,5)

(iii) distance formula. root(5) units

(iv) using perpindicular distance formula where...a=2, b=-1, c=-1, x=0, y=3
gets 4/root(5)

(v) A=h/2 (a+b)

Find distance of AD. which is 3root(5)
A = 1/2 . 4/root(5) . (root(5) + 3root(5))
= 1/2 . 4/root(5) . (4root(5))
= 16 units^2
(have i mistaken here?)


(b)

(i) d/dx = -sinx/cosx = -tanx

(ii) -1(lncos(pi/4))
= 0.3465....
 

karnage

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Rampager said:
370 x 1.2 = 444 (twelfth)


before anyone argues.
Ah.

I wrote something like n > 12.5ish or somethin
Then i just rounded it up to 13.
 

syriangabsta

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Rampager said:
Say what?

2(n+1) - n
------------
n(n+1)


2n + 2 - n
------------
n(n+1)


= n + 2
---------
n(n+1)



I guess not anymore...
.

lol nah, i got that question right. i just didnt look into the answer given in the 1st post, because in the exam i had checked it by substituting n for 2. so yeah. full marks is still there :) too bad i screwed up some later q's :(
 
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Question FIVE:

a) Integral (1-6sin3x) = [x - (-6cos3x/3)] + c
y = x + 2cos3x + c​
When x = 0, y = 7​
7 = 0 + 2 + c​
c = 5​
.:. y = x + 2cox3x + 5​

b) i) x is between -.5 and .5
ii) 19/40

c) i) 6000
ii) 0.2986
iii) 298.6 lux/m
 

farkmedead

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Rampager said:
Say what?

2(n+1) - n
------------
n(n+1)


2n + 2 - n
------------
n(n+1)


= n + 2
---------
n(n+1)



I guess not anymore...


Question 4 b)
50 x 1.2 = 60 (first application)
60 x 1.2 = 72 (second application)
72 x 1.2 = 86.4 (third)
86.4 x 1.2 = 103.68 (fourth)
103.68 x 1.2 = 124.416 (fifth)
124.416 x 1.2 = 149.2992 (sixth)
149.2992 x 1.2 = 179.159 (seventh)
179.159 x 1.2 = 214.49 (eighth)

continuing on...

214.49 x 1.2 = 257 (ninth)
257 x 1.2 = 308.86 (tenth)
308 x 1.2 = 370 (eleventh)
370 x 1.2 = 444 (twelfth)


before anyone argues.
I FAIL THAT SHIT AHHHHH * SEE U ON THE NEWS AS THE SUICIDAL KID.
 

emo-kid-91

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Arithela said:
whats the answer to 7c?
well, we're not there yet. but i spose i can kick my chugging brain into gear.

i. complete the diagram.
ii. p (gg) + p (gxg) + p (xgg) = 1/9 + 2/27 + 2/27 = 7/27
iii. 1 - p (gg) - p (xx) = 1 - 1/9 - 4/9 = 4/9

yeah?

and i have to say, xena and gabrielle? lol! like gabrielle could beat xena.
 
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