Recent content by workerant

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    Slope Fields: Understanding & Application

    http://www.math.rutgers.edu/~greenfie/webstuff/pdfstuff/w6W.pdf is the problem For the first part, I believe it is just tracing, right? I look at the line at (0,1) and then follow it, but it's a little confusing. Next It says how many critical points...well a critical point is when it is...
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    Proving Closure of Set T: f(x)=g(x) on Closed Domain [a,b] in R

    I wrote that before I saw the other post you made to set delta equal and use definition.
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    Proving Closure of Set T: f(x)=g(x) on Closed Domain [a,b] in R

    Well, then for the complement, there is a neighborhood (x-eps,x+eps) that is contained in T since there are infinitely many points on our domain such that h(x)=/=0 because of the fact that h is continuous.
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    Proving Closure of Set T: f(x)=g(x) on Closed Domain [a,b] in R

    Thanks Hmm...okay...so an open set is one where if x belongs to the set T, then there is a neighborhood Q of x that is contained in the set T. So if T={x: f(x)=/=g(x)}, then we can find a neighborhood of x of T , namely (x-eps,x+eps) that is contained in T. Well...obviously if the function...
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    Proving Closure of Set T: f(x)=g(x) on Closed Domain [a,b] in R

    Suppose f:[a,b]--> R and g:[a,b]-->R. Let T={x:f(x)=g(x)} Prove that T is closed. I know that a closed set is one which contains all of its accumulation points. I know that f and g must be uniformly continuous since they have compact domains, that is, closed and bounded domains. Now T is the...
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    Can you check this proof please: sets?

    thanks guys...I actually I did include such a line in my formal write-up so thanks
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    Can you check this proof please: sets?

    Well, then can I say to assume that because I am trying to do a proof by contradiction. I'm confused by what you are saying...I should say A=B=C=D=R and then what? I'm not sure I follow...is the rest okay?
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    Can you check this proof please: sets?

    Homework Statement A,B,C,D are sets. Prove that if C is contained in A and D is contained in B, then C∩ D is contained in A∩ B. Homework Equations The Attempt at a Solution Let x be any element. Then There exists (x that belongs to C∩D) and (x does not belong to A∩ B) So...
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    How can I calculate the work for different volumes of cylinders underground?

    I got it since the volume of a cone is (1/3)* pi* r^2* h and since we are looking at a cone in this problem and we need to integrate the volum*density*g.
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    How can I calculate the work for different volumes of cylinders underground?

    Ok great...thank you very much for your help. The one last thing is...so we don't include the 1/3? That's because we already used it when finding r(h), correct? (just want to be completely sure).
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    How can I calculate the work for different volumes of cylinders underground?

    Ok so I see it as a line...We have pts. (0, sqrt 27) and (10,0) so the slope is: -sqrt(27)/10 And so r(h)= -sqrt(27)/10*h + sqrt(27) And I suppose the other cone would be found in a similar manner...just the points would be (10,sqrt 27) and (0,0) Is that correct? And if so, I'm...
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    How can I calculate the work for different volumes of cylinders underground?

    Ok, that's what I said, that r=sqrt(27) makes them equal to the cylinder. Now comes the part where I'm confused.
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    How can I calculate the work for different volumes of cylinders underground?

    I will take g=10 for simplification purposes. For the cylinder, we have it as integral (0 to 10) 270000* pi* h dh= 13500000* pi J Now we look at the inverted cone and we have integral(0 to 10) 30000 * pi * r^2 * h dh But my problem is, how do I find what r is for the cone? Do I...
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    How can I calculate the work for different volumes of cylinders underground?

    Homework Statement http://www.math.rutgers.edu/~greenfie/mill_courses/math152/pdfstuff/w2.pdf problem 2 Homework Equations Work is the integral of force.. The Attempt at a Solution Problem 2: Basically I know how to calculate the work for the cylinder. Since they have...
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