Recent content by jenuine

  1. J

    Find P[X>Y | X<2Y] of iid variables

    Let X and Y be independent exponentially distributed random variables, each with mean 1. Find P[X>Y|X<2Y] I know I must use conditional probability, but I can't simplify it enough to integrate.
  2. J

    Partial Differential Equation: Can f(u) Satisfy the Equation dz/dx - dz/dy = 0?

    Consider the partial differential equation 2dz/dx-dz/dy=0 Show that if f(u) is a differential function of one variable, then the partial differential equation is satisfied by z=f(x+2y) 3. The Attempt at a Solution : Change of variables? No idea :S
  3. J

    Surface level of a curve, does it influence the tangent plane?

    Well for instance f(x,y,z)=xy+xz+xyz. Then the level surface f=10 would be xy+xz+xyz=10. I am just wondering whether this level surface will influence the equation of the tangent plane. If so, how do I find it with respect to that level surface.
  4. J

    Surface level of a curve, does it influence the tangent plane?

    Homework Statement Does the surface level of a curve influence the tangent plane of that curve? If so, how do I find the tangent plane specific to that level?
  5. J

    What is T-Invariant? - Example & Explanation

    What is T-Invariant? The attempt at a solution: TW1 belongs in W, but what does that mean? Can anybody give me an example along with an explanation?