****Leaving Certificate: Higher Level Maths Discussion****

Isitthough?

Nimrod 7 wrote: »

(10, 5) and (38, 5) I think.

how did you get that? I said y=5 and then they gave you f(x) so I let them equal to see where they intersect used -b but I got weird values..Did I do it right or what?

Aspiring wrote: »

If you have the DEB mock on hand see Question 6A. That's exactly how Theorem 13 would come up I'd say.

Yeah I know saw that that's fine but in 2013 2012 etc.. there different so I was just wondering if they changed them or something?

LC.student2014

Do we have to know corollaries? I'm confused about all the things we have to know and know how to prove! :S

jellytots95

If you're asked to prove the sine rule, do you have to prove it both ways, with a triangle with an acute angle and with a triangle with an obtuse angle?

Tesco TripleChicken

Nimrod 7 wrote: »

You don't even have to do any work for it tbh

Wasn't y just 100-23?

And A was just looking at the equation and realising y =A.


Yeah, that's the one.

I think the corollary is just the angles on the same arc bit.

Yeah I did 100-23 and got Y, then I was messing around with it and thought, "no actually A is 73 not Y" and I just got confused I didn't think theyd be the same. Didnt do the rest of the Q anyway so doesnt really matter now

Are one of the 3 theorems guaranteed to come up on Q6? Is there anything else that always comes up? Really need to do decent on P2 to pass maths

Maths Help Needed

Can somebody help me please, what are the 3 theorems everyone is talking about ?
Thanks in advance!

Worried247

I know this is random but does anyone know, if the reqirements for your college course are:
OC3 or HD3 Mathematics and HC3 French
and you fail higher level maths and think you defo would have gotten above an Ordinary c3, is there any way you can like take an exam or an OL exam during summer to get into the course in September without having to repeat your leaving or repeat maths for the year?

Rbrtmry

There's a website that shows you how to do all of the costructions step by step if anyone wants. Just type "Leaving cert geometry constructions" into google and it comes up. I'd post a link but i'm not allowed do that for some reason.

2thousand14

Isitthough? wrote: »

how did you get that? I said y=5 and then they gave you f(x) so I let them equal to see where they intersect used -b but I got weird values..Did I do it right or what?

Yes thats how I did it

TooMuchStudy

Isitthough? wrote: »

how did you get that? I said y=5 and then they gave you f(x) so I let them equal to see where they intersect used -b but I got weird values..Did I do it right or what?

Yeah, you should've gotten numbers to decimals but it says round to the nearest number

hanza123

Rbrtmry wrote: »

There's a website that shows you how to do all of the costructions step by step if anyone wants. Just type "Leaving cert geometry constructions" into google and it comes up. I'd post a link but i'm not allowed do that for some reason.

That site is brilliant you don't any other good ones? For theorems maybe?

jellytots95

Maths Help Needed wrote: »

Can somebody help me please, what are the 3 theorems everyone is talking about ?
Thanks in advance!

I think they're the three ones at the end of geometry.. They're:

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

Let ABC be a triangle. If a line XY is parallel to Bc and cute AB in the ratio s:t, then it also cuts AC in the same ratio

If two triangles are similar, then they're sides are proportional in order

Maths Help Needed

jellytots95 wrote: »

I think they're the three ones at the end of geometry.. They're:

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

Let ABC be a triangle. If a line XY is parallel to Bc and cute AB in the ratio s:t, then it also cuts AC in the same ratio

If two triangles are similar, then they're sides are proportional in order

Thanks very much for the reply do you know what number theorems they are ?
Thanks once again

jellytots95

Maths Help Needed wrote: »

Thanks very much for the reply do you know what number theorems they are ?
Thanks once again

11, 12 and 13 I think

Maths Help Needed

jellytots95 wrote: »

11, 12 and 13 I think

Yes I just looked there and thats the three you named. Is that all the theorems you need to know ?
Thanks.

Saskatchewan

I wonder could we see a 75 mark coordinate geometry question.....

miissjuly

You're all going to PASS/get the grade you want. Don't worry.
Focus on paper 2!

onethreefive

Maths is driving me crazy. Failed paper one i think and trying my hardest to bring it up to a pass. Can someone please tell me how to construct a perpendicular bisector of a triangle. I'm doing the circumcircle construction.

HugsiePie

onethreefive wrote: »

Maths is driving me crazy. Failed paper one i think and trying my hardest to bring it up to a pass. Can someone please tell me how to construct a perpendicular bisector of a triangle. I'm doing the circumcircle construction.

https://www.youtube.com/watch?v=Wvx53scImwk

http://mathworld.wolfram.com/PerpendicularBisector.html

robman60

miissjuly wrote: »

You're all going to PASS/get the grade you want. Don't worry.
Focus on paper 2!

Ok, but I'll be quoting this in August when I don't get an A1. :rolleyes:

onethreefive

I'm on the verge of throwing my maths book out the window. I've spent over half an hour trying to get the perpendicular bisector of a triangle
Thanks for the video it helped but I'm not sure what to do for the second line if that makes sense

HugsiePie

onethreefive wrote: »

I'm on the verge of throwing my maths book out the window. I've spent over half an hour trying to get the perpendicular bisector of a triangle
Thanks for the video it helped but I'm not sure what to do for the second line if that makes sense

Theres a link under the video

That might help

Hotale.com

onethreefive wrote: »

I'm on the verge of throwing my maths book out the window. I've spent over half an hour trying to get the perpendicular bisector of a triangle
Thanks for the video it helped but I'm not sure what to do for the second line if that makes sense

I don't think that question makes sense. "Bi" means two, a triangle has three sides... Unless they want you to split the area? I think to do that you need to split the altitude or something... I'm doing all my P2 study tomorrow.. :P

Aspiring

I'm so glad I did tech graph for the junior cert. Makes all this bisecting of lines and angles and all so much easier.

Ompala

Hotale.com wrote: »

I don't think that question makes sense. "Bi" means two, a triangle has three sides... Unless they want you to split the area? I think to do that you need to split the altitude or something... I'm doing all my P2 study tomorrow.. :P

Off the top of my head... perpendicular bisector refers to splitting one side of a triangle into two equal lengths

Hotale.com

Ompala wrote: »

Off the top of my head... perpendicular bisector refers to splitting one side of a triangle into two equal lengths

The question must be worded terribly so, it's "perpendicular" to only one side and you're not even bisecting the triangle if that's the case.

Aspiring

Yeah you're splitting the sides.
Say you have triangle ABC
Take your compass at A (put the metal part there). With the pencil part, draw an arc that is past halfway between A and B. Now put metal part at B, do the same thing but the other way around, but use the same radius arc. Draw a line between where the two arcs intersect. That's the perpendicular bisection of a line.

Do this for another line (or two if you want). Where the two (three) intersect is your circumcentre.

Daledge

So I'm pretty confident for paper 2 having been one of the small few who's paper 1 went well, but what exactly should I make sure I know for Monday?

Ompala

Hotale.com wrote: »

The question must be worded terribly so, it's "perpendicular" to only one side and you're not even bisecting the triangle if that's the case.

I don't actually know what the question is,, just remember the terminology.
Now you have me thinking, how do you bisect a triangle? Split it into two parts of equal areas? Surely there are infinite ways to do that...

Conchir

There's a website called studentxpress.ie that has the solutions for Paper One up on it. They're going up gradually, up to question 5 at the moment.

Check at your own peril; I can only half remember my answers so it mightn't be great to look at :P

Hotale.com

Ompala wrote: »

I don't actually know what the question is,, just remember the terminology.
Now you have me thinking, how do you bisect a triangle? Split it into two parts of equal areas? Surely there are infinite ways to do that...

Onethreefive posted the question there a whole back I think.

You can't bisect a triangle as far as I know...