My own infix to prefix approach. What do you think?

[Thomas Klemm]

Exploring the Programs in the EXAMPLES Directory
(HP 48G Series User's Guide, page 29-19)

• run the TEACH command
• this creates a directory EXAMPLES in your HOME directory
• within PRGS you will find the program ->RPN
  

I recommend to single-step through the program (see page 29-8).

For your example you will get:
'(2+3)*(4+5)'
->RPN
{ 2 3 + 4 5 + * }


Cheers
Thomas