Recent content by Portishead

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    Proof concerning the union of a finite collection of events

    I posted this post by mistake, please delete this post.
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    Proof concerning the union of a finite collection of events

    I'm using these lecture notes as a guide, just so you can know what assumptions were made for this problem: http://ocw.jhsph.edu/courses/MethodsInBiostatisticsI/PDFs/lecture1.pdf http://ocw.jhsph.edu/courses/MethodsInBiostatisticsI/PDFs/lecture2.pdf I have no idea to be honest.
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    Proof concerning the union of a finite collection of events

    It's intuitively zero and E1 and E2 are mutually exclusive/disjoint events? If either ## P(E_1) ## or ## P(E_2) ## were the maximum, intuitively wouldn't that be less than or equal to the sum of both probabilities since ##P(E_i) \geq 0##? I just don't know how to formally show my conjecture. Is...
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    Proof concerning the union of a finite collection of events

    All I can think of is that: 1) ## 0 \leq P(E_1 \cap E_2) \leq 1 ##, by definition...
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    Proof concerning the union of a finite collection of events

    Thanks for the hint! So when n=2, ##\max_{1,2} P(E_i) \leq P(\cup_{i=1}^2 E_i)## ##=P(E_1)+P(E_2)-P(E_1\cap E_2)## ##\leq P(E_1) + P(E_2) ## Then, assume for when n=k , ##\max_{i\in N} P(E_i) \leq P(\cup_{i=1}^k E_i)## Define ##Q= \bigcup_{i=1}^k E_i## and let n=k+1. Thus, ##\max_{i\in N}...
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    Proof concerning the union of a finite collection of events

    When n=2, my conjecture is that ##\max_{1,2} P(E_i) \leq P(\cup_{i=1}^2 E_i) \leq P(E_1)+ P(E_2) ## by intuition, but I don't know how to write this formally... My induction hypothesis is as follows, right? Then, for all positive integers n, ##\max_{i\in N} P(E_i) \leq P(\cup_{i=1}^n E_i)##
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    Proof concerning the union of a finite collection of events

    Homework Statement Prove that[/B] P(\cup_{i=1}^n E_i) \geq \max_i P(E_i) (1) for n≥1 Homework Equations I know that P(\cup_{i=1}^n E_i) \leq \sum_{i=1}^n P(E_i). The Attempt at a Solution I know when n=1, trivially P(E_1) \geq \max_1 P(E_1) =P(E_1). So I was hoping I could use induction to...
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    Constant acceleration problem with two objects

    rl.blat, can you take an ordinary derivative of that expression? t and t1 are different variables? Also, uh I solved the problem. I minimized v-passenger=x-train(t')-x-passenger(6)/(t'-6)=.20(t')^2/(t'-6) where t' is the time she gets on the train. That function has a relative minimum at t'=12 s...
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    Constant acceleration problem with two objects

    So, wouldn't it be the other way around? Train(t)=.20t^2; Passenger(t)=v(t-6)
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    Constant acceleration problem with two objects

    I don't think so, as it is not given.
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    Constant acceleration problem with two objects

    Homework Statement A train pulls away from a station with a constant acceleration of 0.40 m/s^2. A passenger arrives at a point next to the track 6.0 s after the end of the train has passed the very same point. What is the slowest constant speed at which she can run and still catch the train...
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    Double Integrals: cartesian -> polar and solve

    Do you need help with #13 still?
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