Ti-89 Math Question


#1

All right, i’ve got a simple question:

I’m trying to take the derivative of a function and have my answer spit back to me in pretty print. This isn’t working, and I even change the mode on the calculator to pretty print and it doesn’t help.

So, i.e., if I want to take the derivative of d(x^2,x) I know I should get 2x as my answer in pretty print, but its giving me 548.49 instead…

Please help…

Thanks,


#2

Did you have x set to 274.245?

EDIT: No one checked my shoddy arithmetic? I thought there was something fishy about that number.


#3

no, I don’t believe so… I’m not even sure how to check this =|


#4

what exactly is pretty print? i’ve extensively used my 89 and i’m not familiar with the term. but yeah it does sound as if you have x set to some value. try using a different variable.


#5

^ he does have a point there. the TI graphing calculators do do that sometimes.


#6

http://mrsroberts.com/MathBits/TISection/Voyage/Derivatives.htm

o.o


#7

I think I have values stored for the x and y variables because I used ‘s’ and it worked… Now how to clear variables.

Thanks everyone for helping.


#8

Solved, thanks for the help! I hit [2nd] F1 to get F6, and then cleared all variables.

Thanks for the clue Septimus!


#9

Damn that sounds handy. How well does it do implicit differention?
Im taking Calculus 1 at the moment and I’ve been using EasyCalc for PalmOS on my Treo phone to check my stuff. Prof. recommended either a TI-89 or TI-92. Anyone got any reccommendations for one over the other? I’m looking for a calculator that will last me the entire college career, and as an engineer, I will ALWAYS be taking math.


#10

I thought it might have been something like that. I think on TI-86, if you trace a graph, it will actually sub in the values of the point of your trace into your x-var and y-var.


#11

At that level, you could get a TI-92. (you can just type stuff in on the keyboard) the TI-89 doesn’t have a keyboard, but otherwise it’s pretty much the same thing. I use 89 because it’s legal on more tests and competitions.

Implicit differentiation is another thing you can use… if I remember correctly, its something like: impdif(equation, independent, dependent).

If you don’t want to clear all your variables, you can use “delvar x” to delete stuff. Obviously that one deletes x. F4->4


#12

TI89 is great, still using it in graduate school, had one since freshman year.

However I’ve sort of moved onto matlab ;( because I don’t really need a hand calculator anymore.


#13

The only thing I don’t like about the TI89 is that the cost for the TI89, i could pick up a modern handheld gaming system that could run circles around the TI89 computationally. ;(


#14

Whenever I think of my 89 I think this: Know in Final Fantasy after you beat a boss and you get some uber overpowered item and the classic final fantasy music start to play? That’s how I felt when I got my 89. Its as if i’m in some super dark cave, then all of a sudden I pull out my 89 and its bright as day! It is seriously that good!

Besides, me and my 89 go way back. I would never have passed Calc 3 without it. It also helped me a lot in Linear Algebra to do matrix equations.

Go with the Classic Ti-89 over the Ti-92. The 92 is huge and wouldt probably land you in trouble if your taking an exam. The 89 is more compact and similar to other Ti calculators such as the -83 variants.