1. S

    Order Of Integration Switch

    I've been given the double integral \int_{x= 0}^{1}\int_{y=x}^{3x}xy dydx and instructed to change the order of integration and solve. After solving the given integrals I found they equaled 1. I reasoned that the initial graph is bounded by two lines y=x and y=3x and bounded on the x-axis...
  2. A

    Probability and light switch...

    Hello guys, I hope you can help with this problem: Lets say a light switch is monitored and its state recorded every hour, ie has the light been switched on at anytime in the last hour? yes/no. This result is stored in a database with an hourly time reference. I'm looking for a probability...
  3. R

    number of ways a switch can be set

    i though you could do this with \frac{8!}{4!.4!} but i got the wrong answer. D: i suck at probability
  4. M

    how to switch parameters for double integrals

    This is probably very simple but I don't know why I am having trouble switching the order of integration and the parameters for double integrals. For example, if the x parameters are 0 and pi and the y parameters are 0 and sinx, how would i change the parameters so I express x as function of...
  5. A

    Switch to polars to evaluate integral

    For b>0, a - b > 1, let f_{ab}(x,y) = |xy|^b / (x^2+y^2+1)^a. Use polar coordinates to integrate f_{ab} over \Re^2.
  6. T

    Need help on POW 12: The Big Knight Switch

    The problem is that you have a 3x3 checkboard and you have 2 black knights on 2 corners and 2 white knights on the other corners. The goal is to switch them around in the least amount of moves. The white knights are at the corners where the black knights were and vice-versa. Help me with this...