Recent content by AlmostFamous

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    Cox Regression Help: Finding Data for Analysis

    Don't know if anyone else was looking for this data, but after sifting through hundreds of web pages, I think I've got some, just waiting to see if the tutor okays it. Thanks though to anyone who was helping.
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    Cox Regression Help: Finding Data for Analysis

    thanks, but i'd tried that. I had actually seen this one before, but the data isn't complex enough for the coursework. the main problem i am finding is that there is plenty of data about cox regression, but very little about what data sets they used to do the analysis with in the first place.
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    Cox Regression Help: Finding Data for Analysis

    First of all, I'm not sure if this is the best place to ask this question so if it isn't...sorry. I'm doing a piece of coursework on cox regression, but I'm having trouble finding any data to use. Most of the data I've seen just gives percentages of people in certain groups, which isn't...
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    Finding Volume in Positive Octant using Multiple Integration

    i've looked at this question again, and I don't know what you mean by splitting it up. I've never had a question like that before.
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    Sphere using mulitiple integration

    okay, I've had a go at this and i end up with 2pi\frac{(16-r^2)^2}{4}=32pi between the limits of a and 0, where a is the number I'm trying to find. then i'd go on to substitue a in and solve. could someone tell me if this is right, or have i gone drastically wrong somewhere.
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    Sphere using mulitiple integration

    i was never particularly good with integration by substitution, but i'll give this a go. thanks
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    Finding Volume in Positive Octant using Multiple Integration

    There isn't an order specified, but I would also assume that z would be the outer integral. Am i right in saying that the largest value for z would be 3, so the z limits are 0 to 3?
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    Finding Volume in Positive Octant using Multiple Integration

    okay, I'm not as bad at this as all the questions make me out to be lol here's the question I've got... Find the volume bound by 2x+z=3 and y+3z=9 in the positive octant, i.e. x, y and z >=0 what i tried was finding the limits on y first. i got from 0 to 9-3z for x : 0 to...
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    Sphere using mulitiple integration

    the final integral looks simple enough, but believe it or not...i just can't seem to do it. the more i look at it the more i can't do it. 2\pi\int_0^a\sqrt{16-r^2}rdr could i get a hint as to how to do this? I'm guessing integration by parts, but i can't figure out how to integrate...
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    Sphere using mulitiple integration

    i thought it should be 32pi, but you'd got 32/pi further up in the question, so i was just checking. and asking where the 16-r^2 part came from was a stupid question that i realized the answer to as soon as i clicked on submit reply lol thanks for the help
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    Sphere using mulitiple integration

    shouldn't that be setting it equal to 32/pi not 32pi? also where does the equation \sqrt{16- r^2} come from? is this possible to do in cartesian coords? or is this way just easier.
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    Sphere using mulitiple integration

    I've proved the volume of a sphere using multiple integration but now i need to use that for the following: find a so that the volume inside the hemisphere z=sqrt(16-x^2-y^2) and outside the cylinder x^2 + y^2= a^2 is one quarter of the hemisphere. I'm having trouble even formulating an...
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    Solving Multiple Integrals with Varying Limits

    Thats the way I did it at first, but I got a much different answer. I checked my original work and I got a sign the wrong way and the answer turned out to be rubbish. Got it sorted now though. Thanks alot.
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    Solving Multiple Integrals with Varying Limits

    This is a question I'm having trouble with. Solve this equation for a \iiint \,dz\,dy\,dx = 2/7 I'm new to this code so i'll write the limits here. the first integral sign is between 0 and 1 the second is between 0 and 4-a-x^2 the third is between 0 and 4-x^2-y I've got to...
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