Junior Cert 2010: Maths Paper 1

DylanS09

Colm! wrote: »

OK, it's not a quadratic, sorry.

x²-4x+5 = (x+1)²-4(x+1)+5
x²-4x+5 = x²+2x+1-4x-4+5
x²-4x+5 = x²-2x+2
-6x+6 = 0
-6x = -6
x = 1

EDIT: Waaait that's not what I got in the exam. Either these aren't the right figues, or I ****ed up.

You're name is Colm right??
My maths grind dude's name is Colm too!
I wonder if ye're related???:pac:

bevan619

kevin12345 wrote: »

what did you get for the C) parts for the graph?

Well, I didn't get them parts done...

soccymonster

DylanS09 wrote: »

I feel like some tard now!ha
I didn't get any of the answers ye're calling out!

well if it makes you feel any better, according to deise, you won't do drugs /Pjoke (:P)

DylanS09

soccymonster wrote: »

well if it makes you feel any better, according to deise, you won't do drugs /Pjoke (:P)

Amm...Ok??:pac:

Fergus_

I didn't get any of those answers said in the thread.

*craps self*

Maths is my worst subject

Closed ac

kevin12345 wrote: »

what did you get for the C) parts for the graph?

-4.4 & -0.8?

kevin12345

DKZ wrote: »

-4.4 & -0.8?

-4.5 and 0.5 but they allow +/- a few

Colm!

I don't think the second figure was negative, DKZ, but that looks right

giggsy664

Geo papers are up on examinations.ie, so the maths papers should be up in a few minutes

Colm!

Thanks for the heads up. I'll download it asap
EDIT: Downloaded.

suitcasepink

soccymonster wrote: »

well if it makes you feel any better, according to deise, you won't do drugs /Pjoke (:P)

Shupppppp
:pac:
Dylan thats unless you're a skanger

Jackobyte

DKZ wrote: »

Yeah, quite a few people I spoke to found it kinda hard aswell.

Q1 C (ii) & Q2 C (i) took me ages to get but I ended up with €60,000 and 2%!

bevan619 wrote: »

The petrol went up by 2.5% right?

Went down by 2.5%?

Colm! wrote: »

EDIT: I got 2.5% for petrol and 2% for compound interest (increasing to €2060.45 for second year)
EDIT2: Yup, I got €60,000 for the income question too

Ya, sames

Namabillion wrote: »

€2000 + r% = 2706.66 -25% = 2030

2030 = 75 %
2806.66 = 100%

use compound formula F= P(1+ t r
2706.66 = 2000r
divide by 2000
1.3533333 Which is 35.333%

Tax was on interest earned, not on total

kevin12345 wrote: »

-4.5 and 0.5 but they allow +/- a few

Ya, I got -4.4 and 0.4

Closed ac

Colm! wrote: »

I don't think the second figure was negative, DKZ, but that looks right

EDIT: I think I did say a positive actually.

Colm!

OK that sample answer I posted for DKZ earlier was wrong, retrying here.

-x²–4x+5 = -(x+1)²-4(x+1)+5
-x²-4x+5 = -(x²+2x+1)-4x-4+5
-x²-4x+5 = -x²-2x-1-4x-4+5
-x²-4x+5 = -x²-6x
-10x+5 = 0
-10x = -5
10x = 5
x = 0.5

EDIT2: Wait, that's still looking wrong lol.

2x+5 = 0
2x = -5
x = -2.5

is that it? I forget what I ACTUALLY did now

EDIT2: I know it's one question and probably only a slip, but no matter how many times I redo the question it doesn't fit what I did in the exam :S

Smiley Laura

Anyone else think they could have done with more time?

soccymonster

Your paper looks alright. Not a fan of those evil q.6 parts though.!

Jackobyte

Smiley Laura wrote: »

Anyone else think they could have done with more time?

Ya, 20 seconds more to correct that one question! Damn examiner!:mad:

jhayden

Colm! wrote: »

EDIT: I got 2.5% for petrol and 2% for compound interest (increasing to €2060.45 for second year)
EDIT2: Yup, I got €60,000 for the income question too

Sorry I'm just browsing the boards and haven't done the Junior Cert. There is a small error in the formula above. Surely it should be 1+-3√ 3

giggsy664

Colm! wrote: »

OK that sample answer I posted for DKZ earlier was wrong, retrying here.

-x²–4x+5 = -(x+1)²-4(x+1)+5
-x²-4x+5 = -(x²+2x+1)-4x-4+5
-x²-4x+5 = -x²-2x-1-4x-4+5
-x²-4x+5 = -x²-6x
-10x+5 = 0
-10x = -5
10x = 5
x = 0.5

EDIT2: Wait, that's still looking wrong lol.

2x+5 = 0
2x = -5
x = -2.5

is that it? I forget what I ACTUALLY did now

EDIT2: I know it's one question and probably only a slip, but no matter how many times I redo the question it doesn't fit what I did in the exam :S

-x²-4x+5 = -x²-2x-1-4x-4+5
-4x+2x+4x=-5-1-4+5
2x=-5
x=-2/5

giggsy664

jhayden wrote: »

Sorry I'm just browsing the boards and haven't done the Junior Cert. There is a small error in the formula above. Surely it should be 1+-3√ 3

Not possible. it said all to be Natural numbers (Positive whole numbers), and the number just before the √ has to be the same as the number inside the √

Colm!

jhayden wrote: »

Sorry I'm just browsing the boards and haven't done the Junior Cert. There is a small error in the formula above. Surely it should be 1+-3√ 3

Crap, I didn't notice that.
what the hell. what the hell.

Colm!

giggsy664 wrote: »

-x²-4x+5 = -x²-2x-1-4x-4+5
-4x+2x+4x=-5-1-4+5
2x=-5
x=-2/5

thanks, I don't know what's coming over me right now, that's two questions I've messed up on :S

Caught

Ehm, did anyone else think that there was something wrong on part 5c, on the HL paper? Sorry if its been mentioned.

Colm!

Let f be the function f : x -> -x^2–4x+5, x e R.
(i) Find the co-ordinates of the points where the graph of f (x)
cuts the x-axis.
(ii) Solve f (x) = f (x + 1).

not seeing the problem...

Ally7

Colm! wrote: »

OK that sample answer I posted for DKZ earlier was wrong, retrying here.

-x²–4x+5 = -(x+1)²-4(x+1)+5
-x²-4x+5 = -(x²+2x+1)-4x-4+5
-x²-4x+5 = -x²-2x-1-4x-4+5
-x²-4x+5 = -x²-6x
-10x+5 = 0
-10x = -5
10x = 5
x = 0.5

EDIT2: Wait, that's still looking wrong lol.

2x+5 = 0
2x = -5
x = -2.5

is that it? I forget what I ACTUALLY did now

EDIT2: I know it's one question and probably only a slip, but no matter how many times I redo the question it doesn't fit what I did in the exam :S

I got a half for it too!

Colm!

I'm fairly sure I got a half in the exam.
I'm tracking my way through the paper, I'm after making two major mistakes (that question and the quadratic one I messed up on). They're only blunders though, I'm still on track to do well.. I hope.. :eek:

Ally7

Am I the only one thinking these threads aren't a great idea? I dunno if it's just me but I don't think we're helping ourselves by going over the exam bit by bit.....

Colm!

It's depressing me, but I kind of want to know what to expect in september. I still hope for an A, but if this means that I have to focus paper 2 more, I'll have to do that.
It's helping me organise the weekend study, I guess.

CookieMonster.x

kevin12345 wrote: »

I got -1+1√7 ? I'm most likely wrong :rolleyes:

Hey everyone! Didn't think it was too hard, got the hard ones I've never gotten before right so I'm happy

For that question I got -2 +- 3√3. Dunno if it's right though cuz it had to be a positive number.

Parawhore.xD

CookieMonster.x wrote: »

Hey everyone! Didn't think it was too hard, got the hard ones I've never gotten before right so I'm happy

For that question I got -2 +- 3√3. Dunno if it's right though cuz it had to be a positive number.

I got that too! My theory is that it was origionally a positive number and that the formula was the only reason it's negative so maybe -2+-3√3 is right?
That;s what i got anyway.

Oh crap.
I think I totally got f(x)=f(x+1) wrong.
I freaking proved it instead of solving it...CRAP!