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

Understanding QuasiLinearity

  1. Nov 13, 2012 #1

    I have two questions.

    (1) I am trying to understand how the following function is quasi-linear:

    Code (Text):

    f = min(1/2,x,x^2)
    For it to be quasi linear it has to be quasi convex and quasi concave at same time.

    (2) I think the reason the above function is not concave is cause on a certain interval (0,1) f = x^2 which is convex. Am I correct in my reasoning?

    Thanks guys
  2. jcsd
  3. Nov 13, 2012 #2
    What is the domain of your function?
  4. Nov 13, 2012 #3
    Real numbers R
  5. Nov 13, 2012 #4


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Yes. Which it is.
    Yes, though it would be more accurate to observe that on (0, 1/√2) it is not concave. (min{.5, x/2, x} would have been concave.)
  6. Nov 14, 2012 #5
    This function is monotonic. And every monotonic function is quasilinear.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Understanding QuasiLinearity Date
I Intuitive understanding of Euler's identity? Thursday at 4:52 AM
B Sine/Cosine behaving like a linear function Jan 11, 2018
B Understanding A Middle Ordinate In Terms Of Geometry Dec 31, 2017
I Understanding Cauchy-Schwarz Inequality Nov 26, 2017