Recent content by SolidSnake

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    Prove the work done by F is zero for a curve on a sphere

    Well the work done by F would be zero then since it doesn't effect the "particle" when moving from point a on the curve to point b. I now understand it intuitively. Thank you :) How would i go about proving this though. Would i need to parametrize a curve along the sphere and show that it is...
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    Prove the work done by F is zero for a curve on a sphere

    Well if the force is perpendicular at one point on the surface curve, and the surface is sphere wouldn't the force always be perpendicular to the curve regardless of which curve is chosen.
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    Prove the work done by F is zero for a curve on a sphere

    The force would be going straight outwards, wouldn't it? with the length modified by f(x,y,z). which would mean it was perpendicular to the curve right?
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    Prove the work done by F is zero for a curve on a sphere

    At any point the force would be the vector (f(x,y,z)x , f(x,y,z)y, f(x,y,z)z). Hmm the light bulb still hasn't gone on :(
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    Prove the work done by F is zero for a curve on a sphere

    Doesn't that depend on the function f(x,y,z) ? since the force field will change depending on what that function is.
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    Prove the work done by F is zero for a curve on a sphere

    We've yet to learn Stokes Theorem, though we have learned Green's theorem. But I don't see how Green's theorem would apply here as it is just a specific case of Stokes Theorem for two dimension (correct?).
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    Prove the work done by F is zero for a curve on a sphere

    Homework Statement Prove that if an object moves along any smooth simple curve C that lies on the sphere x^2 + y^2 + z^2 = a^2 in the force field F(x,y,z) = f(x,y,z)(xi + yj +zk) where f is a continuous function, then the work done by F is zero. Homework Equations The Attempt at a...
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    Probability generating function (binomial distribution)

    well i just realized that G(s) = E(s^{y}) = \sum \left(\stackrel{n}{y}\right)(sp)^{y}q^{n-y} is the same thing as (q + sp)^{n} . Also by definition p + q = 1 \Rightarrow q = 1-p which means... G(s) = E(s^{y}) = [(1-p) + ps]^{n}
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    Probability generating function (binomial distribution)

    Homework Statement The probabilty generating funtion G is definied for random varibles whos range are \subset {0,1,2,3,...}. If Y is such a random variable we will call it a counting random varible. Its probabiltiy generating function is G(s) = E(s^{y}) for those s's such that E(|s|^{y})) <...
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    Integration-Lower/Upper sum, Partition problem

    Homework Statement Suppose f is increasing and continuous on [a,b]. Show for any partition P, \int^b_a f(x)dx - L_f(P) \leq [f(b) - f(a)] \Delta xHomework Equations Not sure if there are any . but for people unfamiliar with this notation: L_f(P) = Lower sum for f with the partition P...
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    Finding tangent lines to an ellipse that pass through a given point

    then a point on the ellipse would be (x , root of (36 - x^2)/4 ) correct?. but even then wouldn't that leave me with the same problem when i set m = m
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    Finding tangent lines to an ellipse that pass through a given point

    Homework Statement Find the equations of all the tangent lines to x^2 + 4y^2 = 36 that pass through the point (12,3) Homework Equations the derivative of the ellipse is dy/dx = -2x/8y (I'm not sure if that is correct, i have only recently learned implicit differentiation.) The...
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    AM-GM Inequality: Prove 0 <= A <= B

    :O the light bulb just went on. Thanks a lot :).
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    AM-GM Inequality: Prove 0 <= A <= B

    i added something i forgot to mention earlier. (B-A)^2 = B^2 -2ab + A^2 Assuming that (B-A)^2 = 0 And if i were to rearrange it i'd get B^2 +A^2 = 2ab And then if divided the 2 and took the root i'd be left with B+A/root 2 = root AB That root 2 is still throwing me off tho. :S
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