Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Need help with some problems

  1. Jan 30, 2007 #1
    hey guys i need help with this problem i tried to figure the out but most are homogeneous equations so i dont even know how to start and the newtons law of cooling i have no idea wut to do .thanks

    Attached Files:

  2. jcsd
  3. Jan 30, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    Welcome to the forums aparra2. Firstly, please note that all homework/textbook questions like this should be posted in the homework forums. Also note that you need to show your work before we can help you- forum rules.

    For this question, your image is not clear, and I can't quite read the questions. Perhaps you could type the equations out? If you do, then I may be able to give you hints; but are you sure you don't know where to start? What do you know about how to solve these type of equations?
    Last edited: Jan 30, 2007
  4. Jan 30, 2007 #3


    User Avatar
    Science Advisor

    Is the first equation
    [tex]p\frac{dp}{dt}= 1+ x+ 2y+ 2xy[/tex]?
    If so, are we to treat y as a constant?

    Is the second equation
    [tex](1+ x^2)\frac{dp}{dx}+ 4xp= \frac{1}{1+x^2}[/tex]?
    If so, that is a linear equation. There is a standard formula for finding an "integrating factor". Do you know it?

    Is the third equation
    [tex](p+ t^2y)\frac{dy}{dx}= 2tdt[/tex]?
    If so can we treat p as a constant?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook