Mathematics Marathon HSC 09 (3 Viewers)

Schoey93

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You may have seen similar threads in other forums. In past years students have found it a great way to quiz each other on various areas of the syllabus and share their knowledge in preparation for the HSC Exams so I thought I would start one for the 2009 Mathematics students.

How To Play:
The first person asks a Mathmatics question (maybe one you've had trouble with). The next person answers it then posts another question for the next person then so on.

Tip:
If you feel an area is your weakness then try asking a question on this area to see others responses to it which may help you in your understanding.

1st Question: (Worth 3 marks in 2000 HSC)
  • Find the equation of the tangent to the curve y=2logex at (1,0)
39th Question (guesstimate.)

This is a higher-order question. Note that it requires English language rather than mathematical notation; which is not always necessary for the skilled mathematician.

Question: Explain why a circular function is equal to infinity. (And yes, there IS an answer...)

:)

NOW no taking the piss!! Serious answer only pls .....
 

tashisthebest

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Ahemed wins $100000 in a lottery. He places it in an investment account which pays 9% interest per annum compounding monthly. He plans to withdraw $M at the end of each year immediately after twelfth interest payment and he wants the investment to last 25 years.

i) Write an expression for A1, the amount of money in the account immediately after his first withdrawal of $M.
ii) Write a similar expression for A2
iii) Since A25= 0 find the value of M to the nearest dollar

i couldn't do this question, some one showed me how 2 do it.
of the top of my head tha value of M was close to 10,000 i think.
If you can get this you are friken GENIUS!!!

 
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hermand

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39th Question (guesstimate.)

This is a higher-order question. Note that it requires English language rather than mathematical notation; which is not always necessary for the skilled mathematician.

Question: Explain why a circular function is equal to infinity. (And yes, there IS an answer...)

:)

NOW no taking the piss!! Serious answer only pls .....
because a circle goes around forever, there is no defined beginning or end.
 

eldore44

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Ahemed wins $100000 in a lottery. He places it in an investment account which pays 9% interest per annum compounding monthly. He plans to withdraw $M at the end of each year immediately after twelfth interest payment and he wants the investment to last 25 years.

i) Write an expression for A1, the amount of money in the account immediately after his first withdrawal of $M.
ii) Write a similar expression for A2
iii) Since A25= 0 find the value of M to the nearest dollar
i)100000x1.0075^12 - M
ii)(100000x1.0075^12 - M)x1.0075^12 - M
okay, we can make a series here. But is it both arithmetic and geometric?
 

ninetypercent

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okay, we need a new question.

easy one

Find the set of values of k for which the roots of 2x^2 + kx + 3k - 10 = 0 are equal
 
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eldore44

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does that make sense?

did you mean for which the roots are equal?
 

eldore44

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b^2-4ac = 0
k^2-4.2.(3k-10)
k^2-24k+80=0
quadratic eqtn with k..
cant be bothered anymore.
 

ForrestGump

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b^2-4ac = 0
k^2-4.2.(3k-10)
k^2-24k+80=0
(k-20)(k-4) = 0
k=20 and k=4

Okay how about:

I drive through 3 sets of traffic lights, the probability
that each will be red is 0.25 and green is 0.75
Find the probability that all 3 lights are red.
 

eldore44

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(1/4)^3
=1/64

Now find the most likely combination(in any order) with 6 such lights.
 

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