# Algebra calculators?

1. Aug 12, 2007

### JimmyJockstrap

Is there calculators you can type in eg.

(x+3)(2x-9)(x+4)=y and it can expand and factorise, vice versa for you?

or would you just use a graph calculator to find the roots?

2. Aug 12, 2007

### HallsofIvy

Staff Emeritus
Yes, there are calculators that will do "symbolic" calculations. The TI80 series comes to mind. But it is real good idea to learn how to do them yourself and not depend on calculators!

3. Aug 12, 2007

### JasonRox

That's not even a hard thing to break down and fool around with.

It gets way harder than that. And even then, do it yourself and test it to see if it's correct. Put some time into it.

4. Aug 12, 2007

### robert Ihnot

JimmyJockstrap: (x+3)(2x-9)(x+4)=y and it can expand and factorise, vice versa for you?

Sure, put it into the TI89 and use the "Expand" key and get: 2X^3 + 5X^2-39X-108.

5. Aug 12, 2007

### Integral

Staff Emeritus
my experience (admittedly early in the algebraic calculator time frame) was that the equations displayed on the limited screen were so hard to decipher, that it was only practical to use on simple equations, but then you should not need the calculator to do the the simple stuff.

6. Aug 12, 2007

### robert Ihnot

The screen is not all that good, but if you are interested in things like:

$$(1+\sqrt5)^6 = 576 +256\sqrt5$$, then you get the answer right away.

7. Aug 12, 2007

### mathwonk

remark: calculators are evil. they make you dumber.

think about it, if riding in a car and sitting in front of the tv with a remote makes you fat and lazy and slow, what do you think it does to your brain to use a calculator?

the action is very fast too. one summer i used a calculator to change policy premiums at an insurance firm, and out of habit when i ahd a simple problem to do, instead of adding up the numbers in my head i used the calculator.

by th end oif the summer i could not do squat in my head after leaving the firm for quite a while. and i was a star at doing mental math. so beware. if you laugh at the fat kid who sits in the stands eating a big pizza while you are playing basketball, well mentally that is you, if you are using a calculator, and the fat is in your brain.

so there. now try to enjoy your calculator.

8. Aug 13, 2007

### robert Ihnot

Halls of Ivy: Yes, there are calculators that will do "symbolic" calculations. The TI80 series comes to mind. But it is real good idea to learn how to do them yourself and not depend on calculators!
__________________

Of course, I was not supposing it was better to buy the TI-89 and learn that in order to do simple Algebra!

9. Aug 13, 2007

### FulhamFan3

At the same time I don't want to spend 20 minutes working out an integral I know I can do when a calculator will give me the same answer in seconds. I'm a physicist, not a mathematician. I don't need to work out every problem. I just need to know that I'm capable of doing it.

10. Aug 15, 2007

### Pythagorean

If you have matlab on your computer, it does symbolic math too