# need to confirm some answers: (1 Viewer)

#### fishy89sg

##### Member
i need to confirm the answers for the following questions (any correct answers will be greatly appreciated! )

7 (b) (iii) and (iv)
7 (a) (ii)
6 (a) (iv)
5 (b)
4 (a) (all)
2 (d) (ii)

thanks guys!!

#### Legham

##### Active Member
for 6 a (iv) i just had pi/12 or something. i thought we'd have to use that n.pi + or - cos.alpha crap, but i think the "first pi seconds" was there to piss that off..

4 a (i) about 0.01
(ii) about 0.285
(iii) 0.4ish? can't really remember

2 d (ii) was about 533 point something.

G

#### gaoOO

##### Guest
i can't find my paper, so a brief description will help

i do remember that for the m values in 7, i got 0.8<m<1.2 (or something like that)
and then i got some pretty odd looking fractions in the second part, which were very long decimals.

7a)ii, i'm fairly confident that i got wrong, so i won't post up my wrong answer.

the others, i have no idea what the questions are...

crap, looking at legham's answers, i think i got the same for 4, but different answers for the others

#### fishy89sg

##### Member
Legham said:
for 6 a (iv) i just had pi/12 or something. i thought we'd have to use that n.pi + or - cos.alpha crap, but i think the "first pi seconds" was there to piss that off..
yeh i had pi/4, 3pi/4, 5pi/12 and 7pi/12

Legham said:
4 a (i) about 0.01
yeh i had that

Legham said:
(ii) about 0.285
yeh i had that

Legham said:
(iii) 0.4ish? can't really remember
yeh i had 0.43

Legham said:
2 d (ii) was about 533 point something.
i had 250 less than you O_O i had 283 point something

gaoOO said:
i do remember that for the m values in 7, i got 0.8<m<1.2 (or something like that)
yeh i had that

gaoOO said:
7a)ii, i'm fairly confident that i got wrong, so i won't post up my wrong answer.
i had k = 1/(ne)

G

#### gaoOO

##### Guest
fishy89sg said:
yeh i had pi/4, 3pi/4, 5pi/12 and 7pi/12
argh, that's not what i got. I think i got pi/4, 3pi/4, 11pi/12 and something else

fishy89sg said:
i had 250 less than you O_O i had 283 point something
yeah, i got 283. something too, but i think my answer was wrong.

edit, i think my other solution was 5pi/12, so we have 3/4 solutions that are the same.

Last edited by a moderator:

#### sting24

##### 2 Radical For U
what about 7.a)ii) i got some crazy answer with "e"s

G

#### gaoOO

##### Guest
sting24 said:
what about 7.a)ii) i got some crazy answer with "e"s
k = 1/ne is what fishy had and i had that too. but i thought i made an error on that one.

#### fishy89sg

##### Member
gaoOO said:
k = 1/ne is what fishy had and i had that too. but i thought i made an error on that one.
your answers are respectable, so im assuming youre right, and thus, i am too :wave:

G

#### gaoOO

##### Guest
fishy89sg said:
your answers are respectable, so im assuming youre right, and thus, i am too :wave:
haha, i don't trust my answers on this paper. i don't think i did that well. i was a bit short on time.

#### fishy89sg

##### Member
did anyone get 1.28m and 0.159m for the widths of the paintball for
7 b) iv)

#### Legham

##### Active Member
fishy89sg said:
i had 250 less than you O_O i had 283 point something
Hmm.. well, gaa00 agrees with you, and someone in the general thoughts thread agreed with my answer We'll soon find out lol.

edit: actually, im pretty sure you're right. me and the other girl forgot to add a constant when integrating i think.

Last edited:

#### Vasc0

##### New Member
fishy89sg said:
i need to confirm the answers for the following questions (any correct answers will be greatly appreciated! )

7 (b) (iii) and (iv)
7 (a) (ii)
6 (a) (iv)
5 (b)
4 (a) (all)
2 (d) (ii)

thanks guys!!
2dii) 284m
4ai) Just use binomial n=2
ii) Binomial again except n=20
iii) 1 - (answer in ii + Probability of 1 being green + Prob of 0 being green)

5b)4! x 3! / 6!

6aiv) There were 4 answers to this, i think pi/4, 11pi/12, 3pi / 4 and there was one more, 5pi/12

7aii) This one i got out somehow..

their y values must be equal if they share the common tanget...

ka^n = In(a)

a^n / In(a) = 1 / k

a^n = 1 / nk

And then somehow I got to n = 1 / e1 x k

7biii) 0.72 <= m <= 1.2
iv) to prove it use part i) and let x = range y = 0
and then the widths are something like 1.3 and 1.2 not too sure on that i can't remember

Last edited:

#### fishy89sg

##### Member
Legham said:
Hmm.. well, gaa00 agrees with you, and someone in the general thoughts thread agreed with my answer We'll soon find out lol.
the question was dodgey: it said that the guy was dropping, yet he was 283m (or 533m) above the point that they dropped

#### sting24

##### 2 Radical For U
i just did 7.a.ii then and got down to

nsquared = e/k

but thats not what i wrote in the exam anyway....,

yea and what the deal with 2dii????

#### Vasc0

##### New Member
fishy89sg said:
the question was dodgey: it said that the guy was dropping, yet he was 283m (or 533m) above the point that they dropped
No he wasn't he was below it, the distance given was that moving downwards. It was just positive in the negative direction.

#### fishy89sg

##### Member
Vasc0 said:
No he wasn't he was below it, the distance given was that moving downwards. It was just positive in the negative direction.
Oh. Thank god i didnt act like there was something wrong.

#### Legham

##### Active Member
fishy89sg said:
the question was dodgey: it said that the guy was dropping, yet he was 283m (or 533m) above the point that they dropped
I think you had to take down as the positive direction.. Because a 10e^-0.2t was positive..

G

#### gaoOO

##### Guest
Legham said:
Hmm.. well, gaa00 agrees with you, and someone in the general thoughts thread agreed with my answer We'll soon find out lol.

edit: actually, im pretty sure you're right. me and the other girl forgot to add a constant when integrating i think.
i used the definite integral approach.

probably on the family one i got 1/5, did anyone else get that?

#### vladimirv

##### New Member
What was the answer to the very last question, 7 b iv)
I got something very small like 0.16, and something larger.
I managed to finish the test with about 25 min remaining, and checked my whole paper except for 7 b)
So far nothing wrong i think

#### fishy89sg

##### Member
vladimirv said:
What was the answer to the very last question, 7 b iv)
I got something very small like 0.16, and something larger.
I managed to finish the test with about 25 min remaining, and checked my whole paper except for 7 b)
So far nothing wrong i think
yeh i had 1.28metres and 0.159metres for the two distances....

so are those answers confirmed