1. Not finding help here? Sign up for a free 30min 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!

What does the big F stand for?

  1. May 10, 2006 #1
    What does the big F stand for in eqautions like

    f(x)-sinb=F(a)-F(b) ??

    It's not like the little f in function.
     
  2. jcsd
  3. May 10, 2006 #2
    Typically, textbooks discussing the Fundamental Theorem of Calculus
    refer to F(x) ("big F") as the antiderivative of f(x) ("little f").

    *This link might help :smile:
     
    Last edited: May 10, 2006
  4. May 11, 2006 #3

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    "f(x)-sinb=F(a)-F(b)" makes no sense. Are you sure it wasn't something like [itex]\int_b^a f(x)dx= F(a)- F(b)[/itex]?
     
  5. May 11, 2006 #4
    SO a capital F means the antiderivative of a function?
     
  6. May 11, 2006 #5

    Hurkyl

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    By convention, if we use a lower-case letter to denote a function, we use an upper-case letter to denote its anti-derivative.

    It's not something you have to do -- it's just something that people usually do because everyone else does it and it's convenient.
     
  7. May 11, 2006 #6

    mathwonk

    User Avatar
    Science Advisor
    Homework Helper

    according to some bumper stickers i have seen, it stands for the president.
     
    Last edited: May 11, 2006
  8. May 26, 2006 #7

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    With "_ _ _" after it?
     
  9. May 26, 2006 #8
    I've seen this used as follows
    f(x)=x^2
    g(x)=x/2
    F(x)=f(x)/(g(x)

    Other than that, doesn't ring a bell.

    EDIT: What math class did you see this in?
     
  10. May 30, 2006 #9
    Did you mean to type anything else? I didn't see a closed parenthesis. If it is indeed so, then the F(x) you saw does not refer to any antiderivative, but simply f(x) / g(x). As Hurkyl said below, the antiderivative notation is simply convention, and not a strict rule of mathematics.
     
  11. May 31, 2006 #10

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    That is simply defining F(x) to be f(x)/g(x)- making it clear that the convention "F(x) is an anti-derivative of f(x)" is not being used!
     
  12. May 31, 2006 #11

    arildno

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    Dearly Missed

    Actually, I hereby declare that the following definition of F(x) is unique and unviolable:
    [tex]F(x)=\frac{\pi}{1+\frac{\pi}{1+\frac{x}{e+\pi}}}[/tex]
     
    Last edited: Jun 1, 2006
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: What does the big F stand for?
Loading...