# Calculators TI 89 Titanium Simple Question

1. Dec 21, 2008

It says (the TI site) that the TI-89 Titanium can manipulate symbolically and what not. Well I just have 2 quick questions:

let's say I punch in some equation like $$\frac{dE}{dt}=\dot{Q}-\dot{W}+\sum_i\dot{m_i}h_i-\sum_e\dot{m_e}h_e$$

1.) I could somehow select W (for example) and the calculator would know to solve the expression symbolically for W?

2.) I could then input numerical values for all of the other variables and it would give me the numerical value of W?

Thanks!!!

2. Dec 22, 2008

Anyone have this calculator?

3. Dec 24, 2008

Seriously, answer me. Please So I can buy it for myself for X-mass.

4. Dec 25, 2008

### rootX

I don't know but I think you are asking for way too much ...

I wouldn't rely on calculators for these things

but I see that it does solve DEs
http://www.rowan.edu/open/depts/math/HASSEN/ODE/TI89_for_ODE.pdf

and this says that it can solve for one variable
http://ti-89.org/forums/post-97.html

then there are always limitations.. these equations need to be dumb simple

(I only used it in grade 12 only.. now I have casio fx. It do many conversions and has constant values and solve simple algebraic, quadratic, cubic equations, etc, .. and had it for about 15\$)

Last edited: Dec 25, 2008
5. Dec 25, 2008

Asking way too much? All I want to know is if I punch in a+b+c=d can the calculator return that a=d-b-c

and if d=1
b=1/2
c=1/2

Can I input those and have it tell me that a=0.

I don't think that is too much... or is it? I have never rellied on calculators to do algebra. But as an engineer entering his junior year, I am sick of doing algebra

6. Dec 25, 2008

### rootX

yep, I think so .. see that thread:

"you can use solve() function to do it (in algebra menu), put the equation first, then a comma, the the varible you want to isolate. in your example, it would be: solve(x+y=z,x) and it will return you x=z-y. Similarly, if you want isolate y, put: solve(x+y=z,y) and it will return you y=z-x"

I thought you wanted something like
df/dt = Q(t) + W(t) + sigma (f(t)) + sigma (z(t))

I been using casio for my engineering ...

I would recommend going through all the TI manual:
http://education.ti.com/educationportal/sites/US/productDetail/us_ti89ti.html?bid=6

and comparing it to what you will be doing.. and if your TI calculator would be allowed in the finals.

7. Dec 25, 2008

Cools! thanks for the links!

8. Dec 25, 2008

### asdfggfdsa

Yes, I own one (for ~4 years now), and yes, it will do what you want (use the solve, nsolve, and desolve functions). Also, if you get it, download this package and install it on your ti.

Merry schnappsmas.

9. Dec 25, 2008