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Maths Game! (1 Viewer)

Lazarus

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Just taking a chance to introduce the LaTeX equation editor. :)

It appears in maths and physics forums at the bottom of a thread just above the quick reply box.

Type out your equation, then just click "copy to document".

The last question was - find all real x such that:



edit - obviously the equation editor takes a bit of getting used to
 

shaon0

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You're solutions correct.

Question:
S [limits:a to -a] sqrt(a^2-x^2) dx
I'll give a hint. Use x=cos(u) as a substituion.
Solution is:
Let x=acos(u), dx=-asin(u) du

[Modulus-ed to find area]
Note: arccos(1)=0, arccos(-1)=pi
 
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kurt.physics

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cbb posting up a question sum1 pls do it for me =D
My one is still here

kurt.physics said:
The side AB of a triangle ABC is a diameter of a circle of radius R, and C lies on this circle. The angle bisector of angle BAC meets BC at E and then the circle at D. When produced, AC meets the circumcircle of triangle CED at F. If BC = a, express CF in terms of R and a.
where the circumcircle is the circle that touches all 3 points on triangle CED. (circumcircle stuff is in cambridge :p)
 

KFunk

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Super cool addition. I've been hoping for a while that LaTeX would be added to the forums. This might attract me back here.

 

h3ll h0und

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isn't it obvious that he is, hes only going into yr11 this year, and he has allready finished the entire 2/3 unit course for the hsc. thats friggen crazy being so far ahead
LOL ... i noe bored.of.u in real life....hes not an accelerant but extremely smart....he does all that stuff at home and studies until 2am (starting straight after coming back from school) ....lol i cud see y ppl wud think he's an accelerant xD
finishing the extension course b4 starting prelim mite sound crazy to some but i dont think it is....if ur good at maths and have a genuine interest u wudnt give a crap and just go on ahead and practice and practice...just like if u had a keen interest in tennis or cricket ud practice and practice.
lol bored.of.u is very modest as well xD he wud call someone like me hu is really dumb compared to him smarter then hiim o_O
 

bored.of.u

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LOL ... i noe bored.of.u in real life....hes not an accelerant but extremely smart....he does all that stuff at home and studies until 2am (starting straight after coming back from school) ....lol i cud see y ppl wud think he's an accelerant xD
finishing the extension course b4 starting prelim mite sound crazy to some but i dont think it is....if ur good at maths and have a genuine interest u wudnt give a crap and just go on ahead and practice and practice...just like if u had a keen interest in tennis or cricket ud practice and practice.
lol bored.of.u is very modest as well xD he wud call someone like me hu is really dumb compared to him smarter then hiim o_O
h3ll hound i appreciate your kindness but i also know you outside of school and i wouldnt call u dumb, your pro physics and math man...and i need my sleep 2am is rare on school days. =D
 
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addikaye03

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Here's one for you chumps, factorise:

x^5 + x^4 + 1
x^5 + x^4 + 1
x^5+x^4+x^3-x^3+1
x^3(x^2+x+1)-(x^3-1)
x^3(x^2+x+1)-(x-1)(x^2+x+1)
(x^3-x+1)(x^2+x+1)--- i think this is what ur looking for

(x^3-x+1)[(x+1/2)^2+3/4]
(x^3-x+1)[(x+1/2)^2-3i^2/4]
(x^3-x+1)[(x+1/2-rt3i/2)(x+1+rt3i/2)]--Optional, prob could have more done to it but cbf

Question: From Coroneos, Find the indefinite integral using the substitution stated, /int e^(tanx+1)/cos^2x dx, using the sub u=tanx+1
 
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azureus88

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[maths]\int{e^{x+e^x}}\,dx = \int(e^x)(e^{e^x})\,dx = \int e^{e^x}\,de^x = e^{e^x} + C [/maths]

New Q: 8 players make the quarter finals at Australian Open. The winner of each quarter finals plays a semi finals to see who enters the final.

(a) Assuming that all 8 players are equally likely to win a match, show that the probability that any 2 particular players will play each other is 1/4
(b) What is the probability that 2 particular people will play each other if the tournament starts with 16 players?
(c) What is the probability that 2 particular people will meet in a similar knockout tournament if 2^n players enter?
 
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