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H can I make a function on Ti-basic?

  1. Nov 14, 2007 #1

    Do any one know how can I make a function on Ti-basic?

    What I mean by function is mathematical function IE. f(x)=x^2+3x and then take the value of f(2) and f(3) and store them on a variable.

    I'm trying to program the http://en.wikipedia.org/wiki/Bisection_method" [Broken] on the calculator for my Numerical Analysis class and I need to take f(a) and f(Pn).



    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Nov 14, 2007 #2
    Apparently nobody programs on a TI calculators.

    Kind of obvious why.

  4. Nov 14, 2007 #3


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    Last edited: Nov 14, 2007
  5. Nov 15, 2007 #4

    This evalf() command is not on the ti-89, at least doesn't have the same name and it just what I need.

    Thanks Ranger
  6. Nov 15, 2007 #5


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  7. Nov 16, 2007 #6
    You say that it is a TI-89?

    I am quite sure that the TI-89 allows you to actually define functions. I do not remember exactly where in the interface you do this, and I cannot find my TI-89 right now. However as I remember it, in the menu where you can create programs, you can also create "functions". Functions are like programs, but they return a value. This means (1) you can call them like functions from the interpreter prompt, which is what you seem to want to do and (2) you can call them from other programs the way functions in a normal programming language would work. Look in the menus, do you see what I am referring to?
  8. Nov 16, 2007 #7
    Yes, Coin there is a way to define a function actually is Define like this

    :Define f(x)=Funct
    : /*Function of x*/

    But for some reason when i try to run the program, I get an error message telling me that I didn't define variable. :confused:

    I had read the manual a couple of times, is not real good source for programming and commands.
  9. Nov 16, 2007 #8
    Thanks Ranger, but the problem is that I'm suppose to make the program. I already manage to evaluate the desire function but is was not a real profesional way. It is kind of lame.

    I made this:

    Code (Text):
    Request "Function: f(x)",f
    Request "Initial point",a
    Request "Final Point",b
    Request "Tolerance",tol
    If Ok=0:Stop
    While abs(a-b)/(abs(a+b)/2)>tol
        [B] p-x
       If fp=0 Then
              Disp "p=",p
       If fa*fp>0 Then
    Disp "f(p)=0, p=",p
    The bold is how do manage to evaluate my function
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