How do I get my Ti-89 to solve 2cosx+1=0
and cos^3x=cosx ? Any help will be apreciated.
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 $\displaystyle \frac{2\pi}{3}, \;\ \frac{-2\pi}{3}$
If c=1, then we have $\displaystyle \frac{8\pi}{3}, \;\ \frac{4\pi}{3}$
and so forth.