How to find domain of a function in HP Prime?

[mobra66]

How do I calculate the domain of a function in my HP Prime?

A few simple examples: If I have f(x) = 1/x, the domain is all values except x = 0, and for f(x) = ln(x) the domain is x > 0.

I can't find a way to do this neither in CAS or "ordinary" calculator mode?

Searching in the help tree and googling does not give me any hints on how to do this, and I can't find it in the manuals?

A friend of mine showed me how his non-HP calculator could do so easily using a built-in function called domain, and I would like to do the same:

[Maké]

Hi!, mobra66:

Try ...

NaN = Not a Number 

You can with SHIFT and PLOT, change the values of X Rng, Y Rng, X Tick and Y Tick.

[mobra66]

Thank you for sharing your idea. However, this does not work well for more complex examples, like f(x)=1/sin(x+pi/3).

[Maké]

Hi!, mobra66:

See, in page 13, of ... http://www.hpgraphingcalc.org/uploads/9/4/3/8/9438994/learning_a_level_maths_with_hp_prime_or_hp39gi...

Note: Is same, for HP39GII and HP PRIME ...

[mobra66]

Thx again, I have also found this document while trying to find a solution. However, the document only describes how you can set up a function with an already known domain. I need the opposite 🙂 given a function, what is the domain?

Below is another example from my friends non-HP calculator to illustrate what I need to do:

[Maké]

Hi!, mobra66:

You can use ... solve

Use CAS.

For x<infinite ... Inequality, is constant, with respect, to x, and result is {x}.

For x>0 ... {x>1}.

Other example :

solve(4-x^2>=0) Enter --> { x>=-2 AND x<=2 }

[mobra66]

To my understanding the domain of 4-x^2 is any number? It is defined for any value of x. So I can't see how solving an inequality describes the domain of this function?

Please refer to https://en.m.wikipedia.org/wiki/Domain_of_a_function

[Maké]

Hi!, mobra66:

See, if serve for you ...

[mobra66]

I think you may have misunderstood my question. I know how to specify the domain on a function. What I need is a method for calculating/deriving/finding the domain itself, given some function as input.
I don't believe the Prime can do this, I cannot find any hints anywhere despite hours of googling and manual reading...
I appreciate your help but I am giving this up for now.

[Maké]

Hi!, mobra66:

For HP PRIME exist DOMAIN and CODOMAIN, of any function. Check this link ... https://books.google.com.ar/books?id=rlpvBgAAQBAJ&pg=PA4&lpg=PA4&dq=how+use+DOMAIN+in+HP+PRIME&sourc...

And check, this site ...

[PDF]Mathematical Exploration with HP Prime - HP Graphing Calculators

www.hpgraphingcalc.org/.../activity_3_exploring_pr... - Traducir esta página

Mathematical Exploration with HP Prime. © HP/Chris Olley 2013. Exploring Projectiles ... This is because the domain for T is pre-set, so the calculator does not ...