Need help with TI-89 Titanium

  1. Hi,

    I'm working out some problems on my TI-89 Titanium, and I've run into a roadblock.

    How do I put a base for a log?

    Thanks a lot.
     
    Last edited: May 20, 2007
  2. jcsd
  3. ln(thing you want the log of) / ln(base of the log)

    As far as I know, that's the only way to do it on a TI. but it's not hard.
     
  4. That's the way I do it; just the standard log change of base formula. So ln(2) is just the log of 2, and ln(2)/ln(10) is log of 2, base 10. You can also see that ln(2)/ln(e), the base e log which is the natural log, will be just ln(2) since ln(e) evaluates to 1.
     
  5. I borrow this thread a little if its okey..
    I got a problem with mine TI-89.
    Whay I want to calculate a root i press "diamond + 9 + x + , + y + enter" which should give me x^1/y. But all i get is what i just pressed, i.e. the answer i get is root(x,y). :confused:
    Please help me.
     
  6. To find a root of x, use the zeros() function. Type zeros(expression,variable), or, alternatively, solve(equation,variable), when the equation is the same expression but set to zero, and the variable is x.

    zeros(4x^2+3x+5,x) or solve(4x^2+3x+5=0,x) returns the roots.
     
  7. Okey, but do you know where the problem for the root function could lie?
    Could it be any setting?

    EDIT: The problem was that I had changed languege... It now works again.
     
    Last edited: May 23, 2007
  8. another way to do log is to log(number, base)
     
  9. That doesn't work for me.
     
  10. I think he has one of those Apps like Omnicalc to upgrade the features kind of. That's also one way you can do it, just with a comma. Change of base requires a little more typing.
     
  11. if you press the yellow Diamond button and then press 7 then log will show up. much less typing for all you lazy people like me
     
  12. i.e. solve(log(x,8)=2/3,x)

    x=4
     
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