Why Is My TI-89 Titanium Giving Unexpected Results for Functions?

[brown.ty]

Hello, I am new to the TI-Titanium and have run into a few rather simple obstacles that are keeping me from answering physics questions in the correct way.

First off, by typing:
\sqrt(5)
the answer comes out to:
=\sqrt(5)
as opposed to 2.2360...
(I believe this is a setting/mode issue)

Secondly, I have a simple trig function:
tanθ=2/1
to solve, I typed:
tan^-1(2/1) as one would do and the result was:
(-90*(((tan^-1(1/2)-pi)/90)-pi)/pi
Now this answer seems to be in radians, and so I changed the setting to degrees..still I get this same answer.
The actual textbook answer was:
θ=63.4°
Why is this happening?

If anyone could tell me what it is I have to do in order for my TI-89 to answer these problems in the way I'd like them to be answered I would greatly appreciate it!
Thanks in advance!

 

[Skrambles]

Try changing the option for results from exact to approximate and see if that works. TI calculators can be very picky when it comes to syntax so be careful about that too.

 

[brown.ty]

That worked! Thank you Skrambles!