1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: PDE Linear Equation

  1. May 14, 2013 #1
    My questions concerns the information in the document.
    I highlighted the portion that is confusing me and a sample problem at the bottom.

    Look at the equation 2.2.4 in the document.
    When I set the function u equal to zero the equation becomes
    0 = 0 + 0 + f(x,t) or f(x,t) = 0.

    Now if you look in the document once more at the underlined green section is says that if f is equal to zero then the equation is homogeneous. However if you read the underlined orange section it says equation 2.2.4 is a nonhomogeneous equation......

    This seems a bit contradictory. Some one please help me understand what they are saying.

    Attached Files:

    • PDE.jpg
      File size:
      31.7 KB
  2. jcsd
  3. May 14, 2013 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    You have shown that L(0) = f(x,t). Since that isn't zero, the equation is non-homogeneous. If that f(x,t) hadn't been in the equation, you would have gotten L(0)=0 and the equation would have been homogeneous.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted