# Thread: Solving for angle problems

1. ## Solving for angle problems

Hello all,
I just started having a problem with my TI-89 titanium. Wondering if any of you can help me out. Whenever I try and solve for an angle it gives me some funky answers, I don't get it. I've been through my mode pletty of times trying to figure it out. Okay here are a couple examples of what I'm getting.
input -> solve(tan(x)=1,x) ans-> x=45*(4*@n22+1)
input -> solve(sin(x)=.5,x) ans-> x=360*(@n21(pi)=1.308997)/(pi) or x=360*(@n21(pi)=.2617994)/(pi)

I don't have anything stored for x. If i input x , then enter I get x as the result.

2. Originally Posted by rex121
Hello all,
I just started having a problem with my TI-89 titanium. Wondering if any of you can help me out. Whenever I try and solve for an angle it gives me some funky answers, I don't get it. I've been through my mode pletty of times trying to figure it out. Okay here are a couple examples of what I'm getting.
input -> solve(tan(x)=1,x) ans-> x=45*(4*@n22+1)
input -> solve(sin(x)=.5,x) ans-> x=360*(@n21(pi)=1.308997)/(pi) or x=360*(@n21(pi)=.2617994)/(pi)

I don't have anything stored for x. If i input x , then enter I get x as the result.

What's your question? You're calculator is giving you the general solution to the equations you've asked it to solve. @n22 etc. are parameters and represent the set of integers.

3. How do I turn those parameters off?

4. Originally Posted by rex121
How do I turn those parameters off?
You can't, because they are part of the answer. If you don't want them, then you need to tell your calculator to solve the equations over a given domain eg. [0, 2pi]. Then you will get numbers, no parameters.

5. It just started doing this... It has never done this before. It has a count going on in that answer. Each time the end half dislplays some type of (4*@n22+1) then next time would be (4*@n23+1), then (4*@n24+1) and so on. I've had this calculator for almost a year and I promise this is not normal.

6. Here is another example: On page 255 of my manual it shows input ->
solve(tan(x)=1/x,x)|x>0andx<1 output -> x=.860...
when I input this exact equation into my calculator I get x= 3.42562 or x = 6.4373 or 59.707

7. Originally Posted by rex121
It just started doing this... It has never done this before. It has a count going on in that answer. Each time the end half dislplays some type of (4*@n22+1) then next time would be (4*@n23+1), then (4*@n24+1) and so on. I've had this calculator for almost a year and I promise this is not normal.
The parameter increments by 1 every time it is used (to distinguish it from the previous parameters).

Originally Posted by rex121
Here is another example: On page 255 of my manual it shows input ->
solve(tan(x)=1/x,x)|x>0andx<1 output -> x=.860...
when I input this exact equation into my calculator I get x= 3.42562 or x = 6.4373 or 59.707
The equation you solved above is over a fininte domain and there is a finite number of solutions. The calculator can tell you each one. In the previous examples you were solving over an infinite domain and there were an infinite number of solutions, these solutions are represented using a parameter.