Re: 2012 HSC MX2 Marathon
First part split the integral as two terms then the integral with the i in it cancels out due to the sine function and we are left with 2x integral of f(x)cos(x). Second part use the property f(x) = f(a-x), add the two integrals, the icos(x) term cancels and the...
They are two different things because we don't care about the output purely. We care about the dice from which the number came.
What you simply did when you counted the {1A,1B} and {1B,1A} case is that you implied 'non-commutativity' in a sense when counting the sets, which is incorrect in...
How does having 6x6 not count having the same number on each side? It does.
Just consider the Cartesian Product: http://en.wikipedia.org/wiki/Cartesian_product
{1,2,3,4,5,6} X {1,2,3,4,5,6} ==> 36 elements in the set of pairs.
I have made a silly error.
Suppose we have a set of N arbitrary numbers and added any two elements of the set, then the probability of having an even total approaches 2/3 as N --> infinity.
However, this is not applicable to this problem because we are taking the sum of the elements of the...
From where did you get this question and its answer?
Because the "Even totals" already amount to 2/3 of the total cases, let alone including those that exceed 7.
Let's look at all the ways we can get an even total:
- Odd + Odd = Even.
- Even + Even = Even
- Even + Odd = Odd + Even = Odd.
So this makes 2/3 of all cases, since we have the same number of odd (1,3,5) as we do even (2,4,6).
So we have:
There are 6 x 6 combinations in total (First die...
hayabusaboston, fortune_cookie is very competent with Mathematics, and I am very confident that he/she would have known what to do without your 'idea'.
Yeah I just thought of it randomly. Sorry if it was too much trouble. I honestly expected a more elementary solution easily found by the average MX2 student =/
Consider a straight line and a piece of string with length L.
In what shape should the string be made to maximise the area bounded by the straight line and the string, given that the string must touch the line at least once?
Give proof.