Maths Theorems

emersyn

Does anyone know if proving a theorem will be a definite question on paper 2, and if so, approximately how many marks will be going for it? It's pretty much the only chapter that I've ignored so I'm trying to decide if it would be worthwhile to study them over the weekend or if I should just revise the things I'm already familiar with :pac:

VG31

Revise them! They didn't come up last year so they're almost definite for this year.

Xgracie

The first 3 are so easy you'll learn them in an hour! The other 2 on the other hand... I havnt touched Pythagoras theorem pretty screwed if it comes up dunno how I'll remember it

ElmW13

There was 20 marks going for the theorem in our pre. Thats over 3% of your total grade. Could be the difference between an A and a B

emersyn

Ok thanks everyone, I'll have a look over them

ECM1234

Xgracie wrote: »

The first 3 are so easy you'll learn them in an hour! The other 2 on the other hand... I havnt touched Pythagoras theorem pretty screwed if it comes up dunno how I'll remember it

When I went to a maths seminar a few weeks ago, we were told by people who correct papers, not to worry about the proof part of the theorems. They told us, to approach them in a similar manner, as we would with labelled diagrams in science. Also most marks on theorems are going for your drawing, so don't worry too much about it!

Liordi

ECM1234 wrote: »

When I went to a maths seminar a few weeks ago, we were told by people who correct papers, not to worry about the proof part of the theorems. They told us, to approach them in a similar manner, as we would with labelled diagrams in science. Also most marks on theorems are going for your drawing, so don't worry too much about it!

The proof is worth 50% of the marks.

ECM1234

Liordi wrote: »

The proof is worth 50% of the marks.

Is it? In that case I have been grossly misinformed!

TheEdgeofGlory

Does anyone know if one of the Constructions can be done with a set square, would you get less marks if you use that method as opposed to the other?.

Liordi

ECM1234 wrote: »

Is it? In that case I have been grossly misinformed!

On the 2012 paper; the theorem was worth 25 marks.
5 marks for the diagram.
Given and to prove were 5 marks.
Proof was 15 marks.

Think theorem is only worth 20 marks now, though, so still 10 marks.

Liordi

TheEdgeofGlory wrote: »

Does anyone know if one of the Constructions can be done with a set square, would you get less marks if you use that method as opposed to the other?.

As long as they don't specify that you need to use a compass you should be fine.

TheEdgeofGlory

Liordi wrote: »

As long as they don't specify that you need to use a compass you should be fine.

Thank you! Do you know which ones are most likely to come up? I'm revising all of them now but I was wondering if there was any particularly important ones?

Liordi

TheEdgeofGlory wrote: »

Thank you! Do you know which ones are most likely to come up? I'm revising all of them now but I was wondering if there was any particularly important ones?

They tend to ask the "HL" only ones, you'd rarely see them asking for you to bisect an angle or something unless there's more than one constructions.

I can imagine either constructing a parallel line through a given point or dividing a line segment into x number of equal parts but I could be wrong.

TheEdgeofGlory

Liordi wrote: »

They tend to ask the "HL" only ones, you'd rarely see them asking for you to bisect an angle or something unless there's more than one constructions.

I can imagine either constructing a parallel line through a given point or dividing a line segment into x number of equal parts but I could be wrong.

Thanks!

JWM12

4 and 6 are really really easy, 9 a tad trickier and then I just get lost on the last two/

Liordi

JWM12 wrote: »

4 and 6 are really really easy, 9 a tad trickier and then I just get lost on the last two/

The last two genuinely wreck my head.
Will have to study them tonight/tomorrow, depending..

I'm not sure if you all were shown it but there's a very easy way of drawing Pythag Theorem Diagram?

emersyn

Liordi wrote: »

The last two genuinely wreck my head.
Will have to study them tonight/tomorrow, depending..

I'm not sure if you all were shown it but there's a very easy way of drawing Pythag Theorem Diagram?

Could you show us? I have no idea how I'm going to memorise the method my teacher gave us before Monday

Eims14

Liordi wrote: »

The last two genuinely wreck my head.
Will have to study them tonight/tomorrow, depending..

I'm not sure if you all were shown it but there's a very easy way of drawing Pythag Theorem Diagram?

I think so something about a square or something isn't it?Ill know it to see it id say/hope :P

Liordi

Sorry if it's blurry, my camera's shocking.


The steps read:
Draw a square 7cm x 7cm
Draw 4 dots 2cm in from the corners
Connect dots in a clockwise motion

I'll try get a better picture.

yaEHya

Liordi wrote: »

They tend to ask the "HL" only ones, you'd rarely see them asking for you to bisect an angle or something unless there's more than one constructions.

I can imagine either constructing a parallel line through a given point or dividing a line segment into x number of equal parts but I could be wrong.

This is what my teacher said:-)

Eims14

Liordi wrote: »

Draw a square .

See I Knew there was squares involved :P

smiles_1998

I hate to be a pain but could anyone post the HL constructions? Our Maths textbook doesn't say which are HL and which are OL...:rolleyes:

Liordi

3, 3a, 7 and 15 are Higher Level.
Rest are needed for both OL and HL.


If you want to go through them interactively (theorems are here as well)
go here.
Think you need to update java and download geogebra.

smiles_1998

Liordi wrote: »

3, 3a, 7 and 15 are Higher Level.
Rest are needed for both OL and HL.


If you want to go through them interactively (theorems are here as well)
go here.
Think you need to update java and download geogebra.

Thank you SO much my maths book is actually atrocious...:rolleyes:

MangoMachine

For anyone having trouble with Pythageros, I found this link very helpful.

http://www.mathsisfun.com/geometry/pythagorean-theorem-proof.html

JWM12

The way I simplified for myself learning them was instead of learning something like |/BAC| + |/ABC| = Whatever, I put shapes in there instead for learning purposes.


I'd have angle C as a square, B as a Dot, A as a tringle or whatever. Write that out and then take the time to consider the |/BAC| stuff carefully, as I found learning it that way to be, as we say, a balls.

JWM12

Liordi wrote: »

The last two genuinely wreck my head.
Will have to study them tonight/tomorrow, depending..

I'm not sure if you all were shown it but there's a very easy way of drawing Pythag Theorem Diagram?

I just hope pythag doesn't come up. I can do his theorum (H squared = O squared + A Squared) but the proof ruins my poor little brain

The way we do it is one big triangle and a perpendicular line from the 90 degree corner to split it into two small ones. Then it'll be the length of AC = BC x BD or something, but its a bit blurred in my head.

Xgracie

MangoMachine wrote: »

For anyone having trouble with Pythageros, I found this link very helpful.

http://www.mathsisfun.com/geometry/pythagorean-theorem-proof.html

Thank you SO much for this! This one is pretty handy too! The book has it way too complicated! http://galwaymathsgrinds.wordpress.com/registered-clients/pythagoras-theorem/

ECM1234

My money, would be on Pythagoras coming up this year..

thetalker

anyone know what topics can come up in p2?
all i'm sure about is that there are constructions and proving theorems

VG31

thetalker wrote: »

anyone know what topics can come up in p2?
all i'm sure about is that there are constructions and proving theorems

Co-ordinate geometry of the line
Trigonometry
Volume/surface area
Probability
Numbers/patterns
Constructions
Theorems
Triangles

There could be more.