***** Leaving Cert Ordinary Level Maths - both papers ****

kierancos

What's everyone studying for paper 2? Not really sure what to do for it apart from trig..

onethreefive

What are the key things to study for paper 2. I'd say i failed paper one. I can't fail maths or it will literally be the worst thing that could happen to me. Feeling awful now after paper 1.

TheRedDevil10

Paper 2

According to the syllabus:

Constructions

16. Construct the circumcircle and circumcentre of a given triangle http://www.mathopenref.com/constcircumcircle.html

17. Construct the incircle and incentre of a given triangle http://www.mathopenref.com/constincircle.html

18. Construct an angle of 60 degrees http://www.mathopenref.com/constangle60.html

19. Construct a tangent to a circle at a given point on it http://www.mathopenref.com/consttangent.html

20. Construct a parallelogram given the lengths of the sides and measures of the angles https://www.youtube.com/watch?v=wVmDKqhC47Q

21. Construct the centroid of a triangle http://www.mathopenref.com/constcentroid.html

onethreefive

TheRedDevil10 wrote: »

Paper 2

According to the syllabus:

Constructions

16. Construct the circumcircle and circumcentre of a given triangle http://www.mathopenref.com/constcircumcircle.html

17. Construct the incircle and incentre of a given triangle http://www.mathopenref.com/constincircle.html

18. Construct an angle of 60 degrees http://www.mathopenref.com/constangle60.html

19. Construct a tangent to a circle at a given point on it http://www.mathopenref.com/consttangent.html

20. Construct a parallelogram given the lengths of the sides and measures of the angles https://www.youtube.com/watch?v=wVmDKqhC47Q

21. Construct the centroid of a triangle http://www.mathopenref.com/constcentroid.html

This is really good!

TheRedDevil10

Theorems

Investigate the following:

7. The angle opposite the greater of two sides is greater than the angle opposite the lesser side.

8. The sides of a triangle are together greater than the third side.

11. If three parallel lines cut off equal segments on some transversal line, then they will cut off equal segments on any other transversal.

12. A line drawn parallel to one side of a triangle divides the other two sides in the same ratio.

13. If two triangles are similar, then their sides are proportional

16. For angle triangle, base times height does not depend on the choice of the base.

17. A diagonal of a parallelogram bisects the area.

18. Area of a parallelogram is the base multiplied by the perpendicular height.

20. A tangent is perpendicular to the radius that goes to the point of contact.
If a point T lies on a circle k and a line TP is perpendicular to the radius to T,
then TP is a tangent to k.

21. The perpendicular from the centre of a circle bisects the chord

Corollary 6. If two circles intersect at one point only, then the two centres and the point of contact are collinear.

You do not have to prove any of these theorems but you must understand how they work in order to answer questions.

A7XGirl

zvseire wrote: »

i guessed d anybody know the correct answer?

Yeah the graph was D

Does anyone know if it's possible for questions that are usually in P1 to appear in P2? Such as calculus

Mayo4sam14

Predictions for paper two??

martmikey

Could someone please tell me how to do this question:

Helen has enough credit to download three songs from the internet. There are seven songs
that she wants.

(i) How many different possible selections of three songs can she make?


(ii) If there is one particular song that she definitely wants, how many different selections
can she now make?

PLEASE

martmikey

Could someone please tell me how to do this question:

Helen has enough credit to download three songs from the internet. There are seven songs
that she wants.

(i) How many different possible selections of three songs can she make?


(ii) If there is one particular song that she definitely wants, how many different selections
can she now make?

PLEASE

BQQ

Use factorials.

smtp95

martmikey wrote: »

Could someone please tell me how to do this question:

Helen has enough credit to download three songs from the internet. There are seven songs
that she wants.

(i) How many different possible selections of three songs can she make?


(ii) If there is one particular song that she definitely wants, how many different selections
can she now make?

PLEASE

For part (i) she can buy 3 but there are seven choices. So imagine you have 3 boxes for the songs she can buy. For the first box she has seven choices, for the second she has six and for the third she has five. 7X6X5= 210 different selections

For part (ii). Imagine one of those 3 boxes for the songs is filled, you only have one choice there. So in the second box you will now have 6 possible choices and for the third you will have five. 1X6X5=30 selections

I hope this helps. If you have Active Maths they cover this chapter very well in the book

Troxck

martmikey wrote: »

Could someone please tell me how to do this question:

Helen has enough credit to download three songs from the internet. There are seven songs
that she wants.

(i) How many different possible selections of three songs can she make?


(ii) If there is one particular song that she definitely wants, how many different selections
can she now make?

PLEASE

Use the nCr function on your calculator!

(i) How many ways can she pick 3 songs from 7 songs?

7C3 which is 35.

(ii)She picks a song she particularly likes. Put that aside. She now is left with picking 2 songs from 6
songs.

So it is 6C2 which is 15.

I hope this helps!

hontheroyalz

martmikey wrote: »

Could someone please tell me how to do this question:

Helen has enough credit to download three songs from the internet. There are seven songs
that she wants.

(i) How many different possible selections of three songs can she make?


(ii) If there is one particular song that she definitely wants, how many different selections
can she now make?

PLEASE

I might be wrong but heres my answer:

(i) she can download 3 songs, with 7 options..therefore 7x6x5 as one song is taken out each time

(ii) this time it's 1x6x5 as you have to have one for sure, again multiplying by the remaining songs

martmikey

smtp95 wrote: »

For part (i) she can buy 3 but there are seven choices. So imagine you have 3 boxes for the songs she can buy. For the first box she has seven choices, for the second she has six and for the third she has five. 7X6X5= 210 different selections

For part (ii). Imagine one of those 3 boxes for the songs is filled, you only have one choice there. So in the second box you will now have 6 possible choices and for the third you will have five. 1X6X5=30 selections

I hope this helps. If you have Active Maths they cover this chapter very well in the book

Thanks... Thats what i thought but when i looked up the marking scheme.. This was the answer:

How many different possible selections of three songs can she make?

= 35



(ii) If there is one particular song that she definitely wants, how many different selections
can she now make?

= 15

Aarong9224

FlyingIrishMan wrote: »

I got a markup of around 75% too.

The total he made from selling 22 sets at normal prices + the 3 remaining sets discounted at 20% was around 2100. And then I just got the percentage difference between the original 1250 and the new total with the discounted sets.

I also got that , maybe we were right

zvseire wrote: »

i guessed d anybody know the correct answer?

Correct answer was D

smtp95

martmikey wrote: »

Thanks... Thats what i thought but when i looked up the marking scheme.. This was the answer:

How many different possible selections of three songs can she make?

= 35




(ii) If there is one particular song that she definitely wants, how many different selections
can she now make?

= 15

Hmmm... :P

I think we're right because with seven choices and three possible songs there would be a lot of possible combinations, not just 35.

But if that's what the marking scheme says well... Damn permutations

aleatorio

smtp95 wrote: »

Hmmm... :P

I think we're right because with seven choices and three possible songs there would be a lot of possible combinations, not just 35.

But if that's what the marking scheme says well... Damn permutations

HL student here,
It's because the 210 combinations are including the different orders of the songs, as in 1,2,3 and 3,1,2 - they're the same songs downloaded, just a different order, so 210 is not correct

The correct answer is 35 because 7choose3 is
7! Divided by 3!((7-3)!)
The formula for nchooser is n!/(r!((n-r)!)
Which gives 35

Then for the second part, it's 6choose2 because one has already been chosen, which using the above formula gives 15

smtp95

aleatorio wrote: »

HL student here,
It's because the 210 combinations are including the different orders of the songs, as in 1,2,3 and 3,1,2 - they're the same songs downloaded, just a different order, so 210 is not correct

The correct answer is 35 because 7choose3 is
7! Divided by 3!((7-3)!)
The formula for nchooser is n!/(r!((n-r)!)
Which gives 35

Then for the second part, it's 6choose2 because one has already been chosen, which using the above formula gives 15

Ahh alright, I get it now. Thanks. That's what I do OL for :P

coffeelover95

Dee15 wrote: »

Just realised I forgot to write in my calculator information on the front of the paper, is that important?!

I forgot too! I asked my maths teacher though and she said it was okay so don't worry about it

Rainydays212

Do you think they will give us an easier paper two? So nervous for Monday..:/

onethreefive

Rainydays212 wrote: »

Do you think they will give us an easier paper two? So nervous for Monday..:/

My future is relying on the hope that it will be easier..

Rainydays212

onethreefive wrote: »

My future is relying on the hope that it will be easier..

Me too !!!! Oh lord..why do they do this to us

miissjuly

Guys I just checked the answers got around a B on Paper 1 so hopefully I can get an A with paper 2. As if 60/50 points is going get me 550 points.. *sighs*

neonmaria

im really worried about probability and trigonometry
i used to like trigonometry but the way its done in project maths i hate it

jazz101

miissjuly wrote: »

Guys I just checked the answers got around a B on Paper 1 so hopefully I can get an A with paper 2. As if 60/50 points is going get me 550 points.. *sighs*

Where did you check the answers?

onethreefive

I want to cover as many topics as I can tomorrow. What exactly should I cover in order of importance for paper 2?

RAnderson1995

miissjuly wrote: »

Guys I just checked the answers got around a B on Paper 1 so hopefully I can get an A with paper 2. As if 60/50 points is going get me 550 points.. *sighs*

where did you get the answers?

miissjuly

I cannot post images or URLs because I am new user (?) been using more than a year thanks boards!! I could send you all as a message if you want?

kev44

miissjuly wrote: »

Guys I just checked the answers got around a B on Paper 1 so hopefully I can get an A with paper 2. As if 60/50 points is going get me 550 points.. *sighs*

Can you type the url?

delaad

smtp95 wrote: »

Ahh alright, I get it now. Thanks. That's what I do OL for :P

Pretty certain combinations were dropped from the course 2/3 years ago.