Start the Maple program. Please note that the text you enter will appear in red on the screen, and system responses will appear in blue. If you forget the semicolon, you can put it on the next line. Notice that Maple always tries to do exact rational arithmetic. The evalf command evaluates numerical results as floating point.
Maple can do floating point arithmetic to arbitrary precision.
Here the result to be evalf'd is the 3rd one back. That is as far back as you can go. Maple knows several special constants, whose names you should avoid using as variables. The name of this one is Pi, not pi. The default precision for floating point is 10 significant digits.