We're going through the entire paper, posting answers. (1 Viewer)

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hairej1

New Member
agreed again i got 8
yayy me too!
this is reassuring hahha

Goody Proctor

New Member
Mongoz said:
someone plZ show how u got 7a and 7c
7(a)

Solve: lnx - 3/lnx = 2

multiply by lnx..
(lnx)^2 - 3 = 2lnx
let lnx = a, making it a quadratic
a^2 - 2a -3 = 0
(a-3)(a+1)=0
therefore a = 3 , a = -1 ...but cant have a negative log, so just 3
3 = lnx
x=e^3 (put it into equation to check and it works)

7(c) was posted above already I think..

erm

Member
ronda said:
e cubed is a solution however 1/e is also another solution as its lnx = -1 which does have a solution
+1

teurino

New Member
100000 x 1.005^n - M (1+1.005+1.005^2... + 1.005^n-1)

is that an alternative to answer given in pdf file with hsc 08 answers?

sportylake

New Member
LiLBoBo said:
think about it. if it comes to 12.5, then if its less than 12.5 you won't get at least 400, therefore it has to be 13 terms,
exactly. spot on.

christiina.h

New Member
what the hell

that series one is def 12

if you sub n=12 back into the sum formula then you get over 400
plus because the first term is actually n=0 because it hasn't been zoomed, hence why people got the final answer as being n>12.5 or whatever it was, but the answer is 12 times