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Reply 2000
Original post by joostan
Seems legit, :biggrin: I'd have factored out the x, rather than playing with the division, and maybe put some brackets around the LHS in the first line, but otherwise, a good solution.
:congrats: +rep :smile:

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Oh yeah :L Thank you for helping me out haha +rep to you to!
Yeah it really is, it makes formulas much easier understand online

I'm gonna redo the whole question once more on paper so that i'm able to apply it in other ones :smile: you've been awesome haha, I would of gotten inpatient by now
(edited 10 years ago)
Original post by tigerz
Oh yeah :L Thank you for helping me out haha +rep to you to!
Yeah it really is, it makes formulas much easier understand online

I'm gonna redo the whole question once more on paper so that i'm able to apply it in other ones :smile: you've been awesome haha, I would of gotten inpatient by now


Lol, Cheers :biggrin:

Spoiler

Had the beauty of this question come up in an FP3 paper I was doing earlier:

"Prove that artanhx=12ln1+x1x artanhx = \frac{1}{2} ln\dfrac{1+x}{1-x} "

True to form, I absolutely butchered it instead of doing it "nicely"... :lol:
Original post by DJMayes
Had the beauty of this question come up in an FP3 paper I was doing earlier:

"Prove that artanhx=12ln1+x1x artanhx = \frac{1}{2} ln\dfrac{1+x}{1-x} "

True to form, I absolutely butchered it instead of doing it "nicely"... :lol:


Looks like you butchered the LaTex

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too :laugh:
Original post by joostan
Cao means correct answer only.
I'd usually go to 3sf, maybe 2dp if it rounds nicely, unless otherwise specified :smile:


Ahhh, okay! Thanks :biggrin:
Reply 2005
Original post by joostan
Lol, Cheers :biggrin:

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Haha no problemo, you deserve it
May I have another q please :smile:
Although I won't be attempting it till 8.30pm so no need to rush, gotta go tkd :smile:
Original post by Westeros
Ahhh, okay! Thanks :biggrin:


NP :smile:
Original post by tigerz
Haha no problemo, you deserve it
May I have another q please :smile:
Although I won't be attempting it till 8.30pm so no need to rush, gotta go tkd :smile:


Lets go for something a bit different.
Show that:
n1Cr1+n1Cr=nCr^{n-1}\mathrm{C}_{r-1} + ^{n-1}\mathrm{C}_{r}=^n\mathrm{C}_r
Original post by joostan
Looks like you butchered the LaTex

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too :laugh:


What spelling mistake did I make? :confused:
Original post by DJMayes
What spelling mistake did I make? :confused:


I bet he thinks it's "arctanh x" :teehee:
Original post by justinawe
I bet he thinks it's "arctanh x" :teehee:


Well, that would teach him a lesson for being a grammar nazi. :lol:
Screen shot 2013-05-22 at 17.26.44.png
Can someone help me with these C2 logs questions from the Solomon Paper A. Thanks!
Original post by Westeros
Screen shot 2013-05-22 at 17.26.44.png
Can someone help me with these C2 logs questions from the Solomon Paper A. Thanks!


What part?

Posted from TSR Mobile
Original post by DJMayes
Well, that would teach him a lesson for being a grammar nazi. :lol:


Original post by DJMayes
What spelling mistake did I make? :confused:


*Gulp* :getmecoat:
Go on bite me :pinch:

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Original post by joostan
*Gulp* :getmecoat:
Go on bite me :pinch:

Spoiler



Sometimes, the best way to save face is by keeping the lower half of it closed. :wink:
Original post by DJMayes
Sometimes, the best way to save face is by keeping the lower half of it closed. :wink:


Not bad :tongue:

Spoiler

Help?

4. At a small branch of the Mid West bank the manager has a staff of 12, consisting of five men
and seven women including a Mr Brown and a Mrs Green. The manager receives a letter from
head office saying that four of his staff are to be made redundant. In the interests of fairness the
manager selects the four staff at random.
a) What is the probability that both Mr Brown and Mrs Green will be made redundant?
Reply 2017
How would you work out the co-ordinates of y = 5 ^ (x - 1) ?
Reply 2018
Original post by Westeros
Screen shot 2013-05-22 at 17.26.44.png
Can someone help me with these C2 logs questions from the Solomon Paper A. Thanks!


t=log3x[br][br]log3x2=2log3xt=\log_{3}x[br][br]log_{3}x^2=2log_{3}x therefore log3x2=2tlog_{3}x^2=2t

Don't know b properly sowwie :frown:

Original post by joostan
Lets go for something a bit different.
Show that:
n1Cr1+n1Cr=nCr^{n-1}\mathrm{C}_{r-1} + ^{n-1}\mathrm{C}_{r}=^n\mathrm{C}_r


Okays, after diinnnneerrr tiiime I shall do this one
(edited 10 years ago)
Original post by joostan
Nonsense: :tongue:
eiθeiϕ=ei(θ+ϕ)=cos(θ+ϕ)+isin(θ+ϕ)e^{i \theta} \cdot e^{i \phi} = e^{i (\theta + \phi)} = \cos (\theta + \phi) + i \sin (\theta + \phi)

eiθ=cosθ+isinθe^{i \theta} = cos \theta + i \sin \theta and eiϕ=cosϕ+isinϕe^{i \phi} = \cos \phi + i \sin \phi

eiθeiϕ=(cosθ+isinθ)(cosϕ+isinϕ)=cosθcosϕsinθsinϕ+i(sinθcosϕ+cosθsinϕ)e^{i \theta} \cdot e^{i \phi} = (cos \theta + i \sin \theta ) \cdot (\cos \phi + i \sin \phi ) = \cos \theta \cos \phi - \sin \theta \sin \phi + i( \sin \theta \cos \phi + \cos \theta \sin \phi)

Equating real and imaginary parts

cos(θ+ϕ)=cosθcosϕsinθsinϕ\cos (\theta + \phi ) = \cos \theta \cos \phi - \sin \theta \sin \phi and sin(θ+ϕ)=sinθcosϕ+cosθsinϕ\sin (\theta + \phi) = \sin \theta \cos \phi + \cos \theta \sin \phi

EDIT: I assume that's what you meant by additional formulae?


Not going to decode that:colondollar:

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