delta and derivatives

Discussion in 'Math' started by AlexK, Jun 1, 2007.

  1. AlexK

    Thread Starter Active Member

    May 23, 2007
    Hello, I have a question

    It is known that the derivative of a discontinuous function at the point of discontinuity is Delta*[F(x+)-F(x-)]
    Now, in order to prove this we need to express the function as a sum of a continuous function ( K(x) ) and a number of steps, so we get:
    F(x)'=K(x)' + Delta*[F(x+)-F(x-)]
    But what should I do with K(x)' ? Can i say it is equal to zero? And if so, why?