Recent content by dj023102

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    Is There a Secret Message Hidden in Shakespeare's Plays and Harry Potter Books?

    So basically divide the number of letters with thenumber of words which apprioxmately equals 3.95 so letters per words.Then starting at the first word (if) count every fourth word so we have(if), (offended), (and) and keep going until you reach (restore). Then count the number of 4letter words...
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    Is There a Secret Message Hidden in Shakespeare's Plays and Harry Potter Books?

    No idea, hence i am asking for some help. But I don't think it is any probability that he has taught during the lecture, i just don't know how to apply binomial, poisson or normal distribution to work it out.
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    Is There a Secret Message Hidden in Shakespeare's Plays and Harry Potter Books?

    Probability gets interesting? Hey guys thought this was an interesting problem that our lecturer purposed: Pick any word in the first few lines and do the following: Let’s say your choice is the word “shadows”. This word has seven letters. The seventh word following “shadows” is “all”...
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    Binomial, Poisson and Normal Probability distribution help

    So just to clarify it for me, this question we can use conditional probability right?: Q2.John teaches two courses in second semester, MTH1122 and MTH1030. Among John’s students 20 percent are MTH1122 students. As a consequence of John’s teaching technique 10 percent of the MTH1030 students...
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    Integrating Exponential Function with Infinite Upper Boundary

    sure i used substitution method. let u = -x^2 then du/dx=-2x, dx=du/-2x this gives the integral of xe^u/-2xdu =pi/2 integrate e^u lower boundary 0 upper boundary infinity then separating the two integral, one integral with lower boundary 0 and upper boundary 1 and the second integral with...
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    Integrating Exponential Function with Infinite Upper Boundary

    i think i worked out. Is the answer (2e-1)*pi
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    Integrating Exponential Function with Infinite Upper Boundary

    if f(x) = pi*xe^(-x^2) integrating this function if the lower boundary is 0 and the upper boundary is infinity is the answer pi*(2e-1). is this right?
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    Famous integral's of exponiental

    hang on there i need more help, stuck on the first part of the question. but i am heading in the right direction now am i?
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    Famous integral's of exponiental

    ah ok! i think i get it. Sorry been looking at the wrong part of the text. So area of cylinder = (exp(-r^2))*(2*r*pi). Is that right?
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    Famous integral's of exponiental

    Ok the height of the exp(-r^2) is, but what about the area? that's is what i having the problem with. i am assuming that i should take the area of the circular disk and times it by the height (exp(-r^2)) and that will give me the volume. But what is the area i should be multiplying by?
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    Famous integral's of exponiental

    Yeah but which area should i use? f(x) = e^(-x^2) or because it is rotated around the z axis i need to make x the subject so f(z) = square root of -In(z) cos after that i need to calculate the volume of the cylinder by integrating the area with lower bound 0 and upper bound infinity. How...
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    Famous integral's of exponiental

    The question ask what is the area of a finite cylinder of radius r when it intersect the bell when the function z=e^(-x^2) is rotated around the z axis (to make the bell). The area is A = pi times (f(x))^2 Is that what the question is asking i think, but is f(x) = e^(-x^2) or because it is...
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    Famous integral's of exponiental

    Gee you guys are difficult :) it's all good just thought it was quicker to use word to type the query up, let's see how i go using latex evaluate[Infinity ]\int[/-Infinity] [e]^{-x^2}. does that make sense? basically integrate e^(-x squared) with upper boundary of infinity and lower...
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    Famous integral's of exponiental

    Hi guys, i have attached my question. really am stuck with this one. apparently it is a famous integral from poisson. Any ideas on where to start would be good. Cheers
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