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HSC 2013 Maths Marathon (archive) (3 Viewers)

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Badsiii

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Re: HSC 2013 2U Marathon

Show that
sec(x) - sec(x)cos^4(x) = sin(x)tan(x)
1 + cos^2(x)
 

Menomaths

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Re: HSC 2013 2U Marathon

Yes I'm quite furious that you managed to answer that

----









integral = (e^x - x) bounded by a and -a
(e^a - a)-(e^-a + a)
e^a -a -e^-a - a = 0
e^a - e^-a = 2a

logify both sides

a+a = log_e(2a)

2a = log_e(2a)

e^2a = 2a

therefore a has to = 0?
 

HeroicPandas

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Re: HSC 2013 2U Marathon

integral = (e^x - x) bounded by a and -a
(e^a - a)-(e^-a + a)
e^a -a -e^-a - a = 0
e^a - e^-a = 2a

logify both sides

a+a = log_e(2a) <---- from here on, its wrong, because you invented your own log law

2a = log_e(2a)

e^2a = 2a

therefore a has to = 0?
(in red)

and if u sub in a =0,
e^2a = 2a
e^0 = 0
1 = 0
trollface.jpg
 
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Badsiii

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Re: HSC 2013 2U Marathon

Equation x^2 - 6x -8y= 23
i) Find the coordinates of the focus

ii) what is the equation of directrix
 

Menomaths

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Re: HSC 2013 2U Marathon

(in red)

and if u sub in a =0,
e^2a = 2a
e^0 = 0
1 = 0
trollface.jpg
ahahhahahah sorry for inventing new things in maths, i have a habit of doing that :<
 
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Re: HSC 2013 2U Marathon

Prove the cosine rule for triangles.
 

spanky125

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Re: HSC 2013 2U Marathon

I posted this in the general thread but it must have been to complex for their simple minds as I did not get a reply.

Sample Question:

John has the choice of either taking Stacey or Kristie to the prom.
The chance of Stacey putting it out is equivalent to x in the equation:
4x-3=8x+1
The chance of Kristie putting out is equivalent to y in the equation:
y+3=2-5y

Which girl should John take to the prom in order to have the greatest chance of getting laid?
 
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RealiseNothing

what is that?It is Cowpea
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Re: HSC 2013 2U Marathon

I posted this in the general thread but it must have been to complex for there simple minds as I did not get a reply.

Sample Question:

John has the choice of either taking Stacey or Kristie to the prom.
The chance of Stacey putting it out is equivalent to x in the equation:
4x-3=8x+1
The chance of Kristie putting out is equivalent to y in the equation:
y+3=2-5y

Which girl should John take to the prom in order to have the greatest chance of getting laid?
Sick negative probability.
 
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