Current Year 11 thread mark III (woo!) / Year 12 2012/13
Discussion for GCSE students, including those studying for IGCSEs and O Levels.
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13Ah, you'll have done better than you expect!(Original post by ElMoro)
Had it today and not gonna lie it was tough. But luckily it was a resit so I have a B to fall back on if it was worse. Got another one this friday which I need to destroy basically if I want any hope of getting an A but I will be pleased with a B overall tbh
Lucky &^%$£
Any plans this summer? 
just make sure you're prepared on Friday then
Not doing much over the summer - I have a huge list of Maths and Physics that I'm going to try and get through. I obviously won't read them all, there's around 50 left on my list! /: I'll also be teaching myself AS Physics, Chemistry, Biology, and A-Level Maths and then I'll also be working! 
got a job last week generate some serious money over the holidays what about you?
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13Seriously, that duck is cute(Original post by usycool1)
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13Exactly the same tbh(Original post by Alexx53)
I thought it went really well, I made a couple of silly errors but I didn't really have trouble with anything.
How did you find it? Made a few silly errors but it was pretty straightforward
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13For a) you use the area of the triangle using the sin thingy:(Original post by SmileAway)
18. Attachment 156377
In triangle ABC,
AC = 8 cm,
CB = 15 cm,
Angle ACB = 70°.
(a) Calculate the area of triangle ABC.
Give your answer correct to 3 significant figures.
I worked this out to be 56.4cm^2, I don't know if that's right or not.
............................... cm2
X is the point on AB such that angle CXB = 90°.
(b) Calculate the length of CX.
Give your answer correct to 3 significant figures.
I have NO IDEA how to do this...I've tried everything, and it doesn't seem to work out even close to the kind of figure I should be getting.
................................ cm
Thank you!
1/2 ab sinc
so I got 56.4 cm2 (3sf)
b)Use the cos rule to work out side AB:
AB2 = 82+152 - 2 x 8 x 15 x cos 70
AB2 = 206.915....
AB= 14.384....
then use the sine rule to work out angle CBA (lol):
sin70/14.384...= sinCBA/8
sinCBA = 0.522...
CBA= 31.507...
then you find cx using sohcahtoa
BC=hyp and CX=opp.
therefore:
CX/15=sin(31.507..)
CX=sin(31.5..)x 15
CX=7.839...
= 7.84cm (3sf)
hope this helps
lol that's so annoying got beaten to it by Alexx53
Last edited by NomNomNom :); 12-06-2012 at 17:44. -
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13Area = 1/2 x base x height(Original post by SmileAway)
Why can't we use the 15cm measurement given to us as the base?
So it would be (56.4/0.5) divided by 15 = 7.52cm??
So if you're dividing by 15 to find a side, that means 15 must be either the base or the height (and the length you find will be the other one).
Eg. If 15 is the height, 7.52 is the base, and if 15 is the base, 7.52 is the height.
However, the length 15 is CB, which in this instance was neither the height (CX) nor the base (AB). -
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13Thanks so much for your help, and yeah, I thought it was the base? How do you know which is which?(Original post by Alexx53)
However, the length 15 is CB, which in this instance was neither the height (CX) nor the base (AB).
Thank you for answering too!(Original post by NomNomNom :))
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From: Current Year 11 thread mark III (woo!) / Year 12 2012/13Are we allowed to speak about the "Edexcel GCSE History A Unit3c : A Divided union" exam now?
I sat it PM
?
How did every1 who sat it found the exam ... if we are allowed to speak about it? :s -
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13When was the exam? If it was today, then no, you can't talk about it yet(Original post by XxKingSniprxX)
Are we allowed to speak about the "Edexcel GCSE History A Unit3c : A Divided union" exam now?
I sat it PM?
How did every1 who sat it found the exam ... if we are allowed to speak about it? :s
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13It was the base, but for the second part of the question I turned the triangle the other way up to make AB the base and therefore CX the height.(Original post by SmileAway)
Thanks so much for your help, and yeah, I thought it was the base? How do you know which is which?
If you try drawing the triangle that way up it might become clearer
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Re: Current Year 11 thread mark III (woo!) / Year 12 2012/13Dunno, shows for me ^_^ , it doesn't matter now i relised V makes a shadow do the point goes to AC to find angel V, hec Sine rule
(Original post by AwkwardLemur)
Alexx, do you have some sort of algebra calculator which does the questions for you?
I do but only for X and them , EG trial and improvement - I safe 10 mins finding the pesky number lol
Last edited by Sheel1; 12-06-2012 at 18:15.
You? 
Any plans this summer? 
got a job last week 
?
