# how do I get my TI-89 to solve for this equation?

Printable View

• Mar 19th 2008, 04:39 PM
SRGTLORD
how do I get my TI-89 to solve for this equation?
How do I get my Ti-89 to solve 2cosx+1=0
and cos^3x=cosx ? Any help will be apreciated.
• Mar 19th 2008, 05:16 PM
galactus
Press F2 and then 'solve'.

Here's a screen capture from my TI-92. It works the same.

The @n1 symbol represents a constant we can call c.

If you enter an integer value for this, then we have a solution which satisfies the equation.

If c=0, then we have $\frac{2\pi}{3}, \;\ \frac{-2\pi}{3}$

If c=1, then we have $\frac{8\pi}{3}, \;\ \frac{4\pi}{3}$

and so forth.
• Mar 19th 2008, 07:33 PM
SRGTLORD
hmmm
how do I change the constant?
• Mar 20th 2008, 12:46 AM
earboth
Quote:

Originally Posted by SRGTLORD
how do I change the constant?

Do you want to use numbers instead of @n1 ? If so:

1. Place the cursor into the line with the results: The results are marked up
2. Press ENTER: The line is copied into the edit line
3. Now you can alter every entry in this line