Higher Level Maths Paper 1 2012 Before/After

DepoProvera · 07-06-2012 11:42pm

Are yous trying to sabotage people or what? It's an argand diagram so it's measured from -180 to 180 (-pi to pi)

diarmo06 · 07-06-2012 11:44pm

AGH, to do or not, that is the question whether it is noblier in the mind to suffer through maths paper one or to take arms against pass and by doing end it.
Still don't know what to do, failed my pres with a solid 38% but all of 12% got when I did paper one. Dominating project though..

reznov · 07-06-2012 11:47pm

This thread is doing more harm than good with all the confusion. Open a book guys! It's there.

DepoProvera · 07-06-2012 11:48pm

http://www.cems.uwe.ac.uk/~klhender/espressomaths/mathcentre/Maths_1st_Aid_Kit/7_4.pdf

I give up lads but if you do as they say you'll get **** all marks in your question. They are thinking of unit circles in trig which is completely different SIGH test a few 3rd and 4th quad coordinates with your calculator THEY WILL BE NEGATIVE VALUES

reznov · 07-06-2012 11:49pm

With Complex numbers you always work from pi. Don't know where this whole 2pi craic is coming from. Positive sense of the x axis and twist anti clock wise.

ei.sderob · 07-06-2012 11:50pm

DepoProvera wrote: »

Are yous trying to sabotage people or what? It's an argand diagram so it's measured from -180 to 180 (-pi to pi)

Nah, works just as well using the unit circle. It allows you to keep the angles positive.

DepoProvera · 07-06-2012 11:51pm

ei.sderob wrote: »

Nah, works just as well using the unit circle. It allows you to keep the angles positive.

Good luck tomorrow mate

Mista · 07-06-2012 11:52pm

ei.sderob wrote: »

Nah, works just as well using the unit circle. It allows you to keep the angles positive.

Yea, I've always used unit circle and it gives the right answer every time..

ei.sderob · 07-06-2012 11:52pm

DepoProvera wrote: »

Good luck tomorrow mate

Thanks BUD:D

Dearbhaile · 07-06-2012 11:53pm

I'm lost.

DepoProvera · 07-06-2012 11:54pm

Probably because they've been 1st or 2nd Quadrant.. read the link I posted above.

ei.sderob · 07-06-2012 11:55pm

No probably because it's just a right way of doing it.

leaveiton · 07-06-2012 11:55pm

http://examinations.ie/archive/markingschemes/2006/LC003ALPO00EV.pdf Marking scheme from 2006. Q3 c(i). Seems to be using the method described above of adding the angle on to pi.

BeanbagBallbag · 07-06-2012 11:57pm

To whom it may concern, you will NOT lose any marks if you use the positive angle in the 4th quadrant rather than -a(reference angle).

Edit: Nor in the 3rd quadrant.

ei.sderob · 07-06-2012 11:57pm

http://www.studentxpress.ie/papers/compsoln2008.pdf

ei.sderob · 07-06-2012 11:59pm

Seeee....if people who had an opinion actually KNEW what they were talking about then there'd be a lot less confusion right now.

leaveiton · 08-06-2012 12:02am

This is why I never understood the whole thing in the first place! But thank you, ei.sderob, you've made everything clear!

DepoProvera · 08-06-2012 12:07am

ei.sderob · 08-06-2012 12:11am

No worries man.

BeanbagBallbag · 08-06-2012 12:15am

To clear things up a bit for everybody;

using the angle θ (theta) such that:

-180° (pi) < θ ≤ 180° (pi)

is just dominant convention. It is not rigid and you will get full marks if you use the full angle.

Dapics · 08-06-2012 12:56am

reznov wrote: »

With Complex numbers you always work from pi. Don't know where this whole 2pi craic is coming from. Positive sense of the x axis and twist anti clock wise.

Ok here's my explanation.

There are a few notable circumstances in which you either must/should add a pi to an angle/radian.

The most notable is seen in trigonometry where graphs of tan, sin and cos are drawn up. In one of these such graphs the number in front of the equation is the range and the number in front of the x behind the sin/cos/tan is the frequency. The range is basically how high the graph goes, the range is how many up's and down's the curve does until it passes 180 degrees. 180 degrees is one pi, 360 is 2 pi, 540 is 3 pi and so on.

It is these graphs which will most likely come up in the exams wherein as stated before you ought/must add a pi.

In Complex numbers i think there are questions in which you have to find a range of values within a certain degree/radian range,most notably and prominently in de moivre's theorem, thats what i think ye all mean.

There are other circumstances but i am growing weary, hope this helped... im off to sleep.

finality · 08-06-2012 1:00am

Dapics wrote: »

Ok here's my explanation.

There are a few notable circumstances in which you either must/should add a pi to an angle/radian.

The most notable is seen in trigonometry where graphs of tan, sin and cos are drawn up. In one of these such graphs the number in front of the equation is the range and the number in front of the x behind the sin/cos/tan is the frequency. The range is basically how high the graph goes, the range is how many up's and down's the curve does until it passes 180 degrees. 180 degrees is one pi, 360 is 2 pi, 540 is 3 pi and so on.

It is these graphs which will most likely come up in the exams wherein as stated before you ought/must add a pi.

In Complex numbers i think there are questions in which you have to find a range of values within a certain degree/radian range,most notably and prominently in de moivre's theorem, thats what i think ye all mean.

There are other circumstances but i am growing weary, hope this helped... im off to sleep.

That's kind of moving towards paper 2 material though.

reznov · 08-06-2012 5:54am

Dapics wrote: »

Ok here's my explanation.

There are a few notable circumstances in which you either must/should add a pi to an angle/radian.

The most notable is seen in trigonometry where graphs of tan, sin and cos are drawn up. In one of these such graphs the number in front of the equation is the range and the number in front of the x behind the sin/cos/tan is the frequency. The range is basically how high the graph goes, the range is how many up's and down's the curve does until it passes 180 degrees. 180 degrees is one pi, 360 is 2 pi, 540 is 3 pi and so on.

It is these graphs which will most likely come up in the exams wherein as stated before you ought/must add a pi.

In Complex numbers i think there are questions in which you have to find a range of values within a certain degree/radian range,most notably and prominently in de moivre's theorem, thats what i think ye all mean.

There are other circumstances but i am growing weary, hope this helped... im off to sleep.

The upper half of your answer = Paper 2, trig.
Lower = Paper 1, complex numbers (what you need today)

cocopopsxx · 08-06-2012 8:35am

This will sound like a stupid question but do you know that identity which means 'it holds true for all values of r', I.e. You can sub in any value for r, how do you know when to use that? :S

waiting4 · 08-06-2012 9:10am

hoping to get 7 questions done, how long should i spent on each?

ei.sderob · 08-06-2012 9:13am

I've got no clue why people still insist on going on about De Moivre's and finding the arguement. Using the unit circle method works for both trig and complex numbers. People who are trying to dispute that clearly only learned off a certain method and don't understand the actual concept. They then try to prove other peoples correct opinions as incorrect in an effort to reassure themselves over their method or ability at maths in general. Give it a rest like. The people who were originally confused got a correct, easier, way of finding the arguement. There's no point to cause anymore confusion.