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:woo:
Reply 2
Original post by dabest2500
Oh right, that book is apparently for "beginners".
I spams slice turns :facepalm2:
It's method is also so unorganised that I don't understand it.

You made me get excited and all :unimpressed:


Sorry :emo:
Original post by joanna-eve
Sorry :emo:


:shakecane:
Ooh, I made it in time for the new thread. :biggrin:
Original post by wcp100
Do the calculation seperately


What do you mean?
Reply 6
Original post by minimus777
Hey :hugs:

Well, if it helps i feel horrible and sort of wish that i'd just got my predicted grades instead. I think that the whole thing was just a case of beginners luck.

You're the super smart one. You can speak over 200 different languages (or thereabouts), worked out the nationality of those people that dabby was talking about just from the spelling of their names, taught me what a Pagan was, and what linguistics is and countless other things.

Oh, and are you the one who said they had an idioglossia? Because i finally got round to googling what it actually means, and if it was you then you are officially one of the coolest people i've known, ever!! :awesome:


:hugs:
Don't! You totally deserve your grades!
Well, I'm not fluent :colondollar: and only studied 4 at school, hopefully rising to 5 soon :colone: I'm just a total linguistics nerd :lol: You know about being streetwise and first aid and stuff!
I am! I believe ML does as well :yep: Thank you, I think it's one of the things that sets me apart from the crowd :lol:
Reply 7
Original post by --emma--
Ooh, I made it in time for the new thread. :biggrin:


Hi! Have you had a good day?

Original post by dabest2500
:shakecane:


:teehee:
Reply 8
It doesn't feel like we've gone through 5 years of secondary school, or not to me anyway :biggrin:
Reply 9
Original post by dabest2500
What do you mean?


She worked it out seperately. Solved it by expanding terms etc. and then equated the two terms
Reply 10
Original post by dabest2500
Yeah, it's time to push for A-Levels :dumbells:


*does the haka*

Original post by Groat
It is for AQA B, it may not be in other specifications. :u:


I think we're doing that spec, but it's likely to be similar for other boards anyway :yes:
Original post by Emissionspectra
Yeah thats right, I messed up getting the -11sin term explain plz :biggrin:


Sure thing. :smile:

Unparseable latex formula:

\mathrmbb{cosec} \theta (3\cos 2\theta +7)+11 = 0



But
Unparseable latex formula:

\mathrmbb{cosec} \theta = \dfrac{1}{\sin \theta}



So:

1sinθ(3cos2θ+7)+11=0\dfrac{1}{\sin \theta} (3\cos 2\theta +7) + 11 = 0

Multiplying brackets out gives:

3cos2θ+7sinθ+11=0\dfrac{3\cos 2\theta + 7}{\sin \theta} + 11 = 0

But cos2A=12sin2A\cos 2A = 1 - 2\sin^2 A (one of the three forms of the cos double angle formulae).

So:

3(12sin2θ)+7sinθ+11=0\dfrac{3(1 - 2\sin^2 \theta) + 7}{\sin \theta} + 11 = 0

36sin2θ+7sinθ+11=0\dfrac{3 -6\sin^2 \theta +7}{\sin \theta} +11 = 0

106sin2θsinθ+11=0\dfrac{10 -6\sin^2 \theta}{\sin \theta} +11 = 0

Multiplying all terms by sinθ\sin \theta gives:

106sin2θ+11sinθ=010 -6\sin^2 \theta + 11\sin \theta = 0

6sin2θ+11sinθ+10=0-6\sin^2 \theta + 11\sin \theta +10 = 0

Additional step of multiplying every term by -1:

6sin2θ11sinθ10=06\sin^2 \theta - 11\sin \theta -10 = 0

:smile:
(edited 12 years ago)
Reply 12
OMG We are year 12s

:party:

This surreal for anyone else?
Guys. Stop filling threads! :frown:

I hope everyone was pleased with their results! :biggrin:

Original post by Maths_Lover
*Maths stuff written with Latex*


Is that A-Level? I think I might just go jump off a tall building.
(edited 12 years ago)
Original post by joanna-eve
Hi! Have you had a good day?


Yep. Saw the Inbetweeners movie with my friend. You?

Original post by BookWormShanti
OMG We are year 12s

:party:

This surreal for anyone else?


Yes! No uniform...free periods...it's scary. :eek:

And finally...NO MORE RE!!! :woo:
Reply 15
Original post by BookWormShanti
OMG We are year 12s

:party:

This surreal for anyone else?


Absolutely! My mum works at the college I'm going to (in a week's time!) and she had to drop something in so I went to the library and it was just so weird that technically that's my school now and everything :eek:
Reply 16
Original post by BookWormShanti
OMG We are year 12s

:party:

This surreal for anyone else?


I'm a year 13. :beard:
Reply 17
Original post by joanna-eve
*does the haka*

I think we're doing that spec, but it's likely to be similar for other boards anyway :yes:


I would've said it's an awful exam, but after that result I can say it's awesome. :colondollar:
Reply 18
Original post by Groat
I'm a year 13. :beard:


With no hair and a ginger beard? :lolwut:
Original post by Maths_Lover
Sure thing. :smile:

Unparseable latex formula:

\mathrmbb{cosec} \theta (3\cos 2\theta +7)+11 = 0



But
Unparseable latex formula:

\mathrmbb{cosec} \theta = \dfrac{1}{\sin \theta}



So:

1sinθ(3cos2θ+7)+11=0\dfrac{1}{\sin \theta} (3\cos 2\theta +7) + 11 = 0

Multiplying brackets out gives:

3cos2θ+7sinθ+11=0\dfrac{3\cos 2\theta + 7}{\sin \theta} + 11 = 0

But cos2A=12sin2A\cos 2A = 1 - 2\sin^2 A (one of the three forms of the cos double angle formulae).

So:

3(12sin2θ)+7sinθ+11=0\dfrac{3(1 - 2\sin^2 \theta) + 7}{\sin \theta} + 11 = 0

36sin2θ+7sinθ+11=0\dfrac{3 -6\sin^2 \theta +7}{\sin \theta} +11 = 0

106sin2θsinθ+11=0\dfrac{10 -6\sin^2 \theta}{\sin \theta} +11 = 0

Multiplying all terms by sinθ\sin \theta gives:

106sin2θ+11sinθ=010 -6\sin^2 \theta + 11\sin \theta = 0

6sin2θ+11sinθ+10=0-6\sin^2 \theta + 11\sin \theta +10 = 0

Additional step of multiplying every term by -1:

6sin2θ11sinθ10=06\sin^2 \theta - 11\sin \theta -10 = 0

:smile:


I forgot to put the denominator as sinθsin\theta XD

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