Solutions (4 Viewers)

[Cloak]

For question 4 (a) i didn't change the answer to pie i just wrote the number and then radians e.g "124 radians" also on the area one i wrote "radians^2", so opinions on if teh answer is right or wrong.

What was the graph for the acceleration 7 b (ii) (iii)

what was 5 (c) (d) (i) (ii)

2 (d)


and for 3 (a) does the little 5 above the sum of sign mean up to term 5 or 5 terms

rest of questions i made stupid mistakes like forgetting how to intergrate, thinking i had to find the year when it was the sum of money and writing music lyrics for answers.

 

[Srixon]

Hey would u get a mark for 4 a) ii) if u put 53 without not decimal places

 

[Cloak]

DOn't worry about my previous posts or questions about radians because i dont no hwo to use a calculator and screwed up anyhow.

 

[Cloak]

Hey would u get a mark for 4 a) ii) if u put 53 without not decimal places

probably get 1 out of 2 marks

 

[ieatdirt]

do you know what i think everyone? i think you are all to worried about the exam, you should relax and study some more maths, so that next time when you have to use maths you will know the answer. i also heard that they're making us do a compulsory maths test to get into uni now, which is fantastic. more maths study for me! i was seriously depressed once i walked out off that maths exam, i seriously enjoyed the study so much, im definitely gona get 100% for the exam no doubt. I wish everyone would love the study like I do, you don't know what your missing out on. Anyway, have fun my future blue collar workers... u will regret not loving the study like i do. Uni will be the greatest time ever, im planning on spending my whole life there and just studying forever. I wish study was an olympic sport, i would easily represent australia and get all the gold medals and be the best studier in the whole world!!!!!!!!!

oh i love the study so much. thank you god for books and exams!!!!!!! I LOVE THE STUDY I CAN'T GET ENOUGH!!!! IM NOT EVEN ASIAN!!!!!!!!!!!!!!!!!!

 

[Cloak]

do you know what i think everyone? i think you are all to worried about the exam, you should relax and study some more maths, so that next time when you have to use maths you will know the answer. i also heard that they're making us do a compulsory maths test to get into uni now, which is fantastic. more maths study for me! i was seriously depressed once i walked out off that maths exam, i seriously enjoyed the study so much, im definitely gona get 100% for the exam no doubt. I wish everyone would love the study like I do, you don't know what your missing out on. Anyway, have fun my future blue collar workers... u will regret not loving the study like i do. Uni will be the greatest time ever, im planning on spending my whole life there and just studying forever. I wish study was an olympic sport, i would easily represent australia and get all the gold medals and be the best studier in the whole world!!!!!!!!!

oh i love the study so much. thank you god for books and exams!!!!!!! I LOVE THE STUDY I CAN'T GET ENOUGH!!!! IM NOT EVEN ASIAN!!!!!!!!!!!!!!!!!!

My Favourite Novel is "On the Road" im a massive beats fan
and i degrade those that read anything by J.K. Rowling.

 

[jennylim]

My Favourite Novel is "On the Road" im a massive beats fan
and i degrade those that read anything by J.K. Rowling.

May I ask why?

 

[andwz]

Gosh ppl
maths is over no more lol
forget abt it

 

[dash87125]

That's what I got, t=0.

I find it hard to comprehend, though that the water is draining the fastest before any time has passed

Mmmm, well this is wot i had,

U cant find y''=0 for an inflexion point

so, u draw the graph after expanding it out

its a parabola and the steepest gradient (ie. fastest rate) is at the end point, t=0

 

[pravski]

solution for 10b

as someone said before, graph it and P = 1 - (areas of triangles)

for the last part, you need to express the areas in terms of t.

This is 1/2 (1-t)^2

since there are two trinalges, P = 1 - (1-t)^2

form a quadratic, solve it with the formula, and since t < 1, you get t = 1/2 (2-sqrt2)

Multyiply by 60, t = 18 min

 

[shobadaynature]

Mmmm, well this is wot i had,

U cant find y''=0 for an inflexion point

so, u draw the graph after expanding it out

its a parabola and the steepest gradient (ie. fastest rate) is at the end point, t=0

I couldn't work it out by maths, so I just put common sense -> t=0, but I can't reli explain it...:S:S

 

[kath-32]

10. (a) (i) I did it the easy way.. subbed A and B into the gradient formula.

that's the easiest way to do it

 

[MarsBarz]

that's the easiest way to do it

There was an even easier way of doing it

10.a.i
y = x²
y = mx+b
Solving simultaneously
x² = mx+b
x²-mx-b = 0
Hence, the roots (A and B) are:
A+B = -b/a = m
A*B = c/a = -b

See it was even simpler.

 

[instantGRAVY]

whats pissing me off.... Q9b)

anyone has an answer?

 

[MarsBarz]

9.b
(i)
Note that I don't know the ascii character for theta so I'll use @ to denote it instead.

AB = 6 (this is given)
/_ DAB = @ (this is given)

First we are asked to find te length of BD.
sin@=BD/6
.:. BD = 6sin@

Now we must show that the length of EF is 6sin³@.
/_DBA = 180-90-@ = 90-@ (angle sum of triangle)
/_DBE = 90-(/_DBA) = 90-(90-@) = @ (complementary angle, notice the right angle).

sin@=DE/(6sin@)
.:. DE = 6sin²@

/_EDB = 180-90-@ = 90-@ (angle sum of triangle)
/_FDE = 90-(/_EDB) = 90-(90-@) = @ (complementary angle, notice the right angle).

sin@ = FE/(6sin²@)
.:. FE = 6sin³@

Not a very elegant solution but it takes virtually no time to do. I just coppied a bit of the diagram and labelled some of the things and had arrows and stuff giving reasons haha.

(ii)
Limiting sum of BD + EF + GH
6sin@ + 6sin³@ + 6sin⁵@ + . . .

a = 6sin@, r = sin²@

S_oo = a/(1-r)
S_oo = 6sin@/(1-sin²@)
S_oo = 6sin@/cos²@
S_oo = 6sec@tan@

#
Well I'm pissed off, I've just found out by doing this again that I got (ii) wrong in the exam. I thought it was BD + ED + EF, so I got r as just sin@ which means I stuffed up. Fucking fucking hell.

 

[MCOLT]

cloak ure a wanker
with the water rate question i used a bit of trial and error and you can see that as t gets closer to 0 the rate increases so i put t=0 i used no calculus what so ever because dR/dt is a constant 2 if i remember

 

[Pixydust*]

ummm guys... it cant be 100/300 * 100/299 * 100/298 * 6

although most of that is correct, i take it that u have decreased from 300 to 298 as each ticket drawn is not replaced... well the point of saying that, is that 100 is not going to be how many tickets are left for the second and third draw... uve taken one out already, remember?

so really, its: 100/300 * 99/299 * 98/298 * 6

dammit!!! i had it going on until i wrote * 3 instead of *6!!!! i forgot that, whilst i had three branches on my probability tree, EACH OF THE FIRST BRANCHES REPRESENTED 2 balls of each colour = 6 total possibilities, not 3 my own stupidity amuses, if not bewilders me.

 

[Pixydust*]

oh i love the study so much. thank you god for books and exams!!!!!!! I LOVE THE STUDY I CAN'T GET ENOUGH!!!! IM NOT EVEN ASIAN!!!!!!!!!!!!!!!!!!

...im confused

 

[SoulSearcher]

...im confused

so am i...

 

[moonshine87]

...im confused

Damm fuckin right.
But see guys, what that arragant person is really telling us is how utterly usless thaty are. What purpose does someone who studies for the rest of their life have, they won't have a job to pay their way through so this will increase taxes for the rest of us through occupying Commonwealth-Supported Places at uni, so their life will eventuate with them being a burden on society. Which is a correct estimation because by the way they were talking they had probably never done a hard days work in their life. Get a life!