Polynomial expansion

[Eddee1]

Everytime I attempt to expand a polynomial on the Hp prime I get 0 as the answer. Someone PLEASE help. For example expanding something like (7X+9)^2

[Maké]

Hi!, @Eddee1:

1) With simplify, in CAS ...

With expand ...

In comparison, with Wolfram Alpha ... http://www.wolframalpha.com/input/?i=expand+polynomial+(7X%2B9)%5E2

2) Select App Solve

See, the sequential images ...

Press, Eval ... 

Press, OK ... 

Press Plot ... 

Note: You can change parameters values for x and y, for see in other image the parabola. 

Now, comparise, with Wolfram Alpha and change, if necessary, in exact Mode ... http://www.wolframalpha.com/input/?i=(7X%2B9)%5E2

[mark4flies]

The name X is reserved for a variable in the Home environment to store a real-valued number. Any expression that uses X will evaluate X. The result of evaluating X is to return the number stored in X. Do you have a value stored in X? Enter X and then press the Enter key. What do you see? You can use variables through the Vars key and manage variables through the Shift-Memory key.

The Home environment is for numeric results. The CAS environment is for symbolic results. You should use the name x (lower case character) instead of X (upper case character) in the CAS environment. The CAS environment is the best place for this kind of work.