HP 48g Graphing Calculator - Manual (Page 258)

A subexpression consists of a function and its arguments. The
function that defines a subexpression is called the top-level function
for that subexpression—it’s the function that’s executed last. For
example, in the expression ' fl+B*C---''D ’ , the top level function for the
subexpression ' B*C ’ is *, the top-level function for ’ E*C.■ ■ ■ ■ [; ’ is .■ ■ ■ ,
and the top level function for ‘ f l + B * C . ‘ i s + .
To collect like
terms
in an algebraic:
Enter the expression onto the stack and press f^(SYMBOLIC)
COLCT. COLCT simplifies an algebraic by doing the following:
□ Evaluates numerical subexpressions. For example,
’ i+2+LOG<10) ' COLCT returns 4.
□ Collects numerical terms. For example, fo.+K+2L COL CT returns
20
D Orders factors (arguments of +) and combines like factors. For
example, LK'’CL'LTtiLL-'''-T*Y ’ COLJ j T returns foi’''''':;T+7)#Y'''''2 '.
D Orders summands (arguments of + or —) and combines like
terms differing only in a coefficient. For example, ' >Li-X+Y+:3*Y '
returns ' 5*Y+Y ‘.
COLCT operates separately on the two sides of an equation, so like
terms on the opposite sides of the equation are not combined.
To expand products and powers in an algebraic:
Enter the expression onto the stack and press (»^fSYIVIBOLIC)
EYF'Fl . EXPAN rewrites an algebraic by doing the following:
□ Distributes multiplication and division over addition. For
example, : B-HC: Exp returns *E-
□ Expands powers over sums. For example. ) EXF
returns
Expands positive power integers. For example.
!E X F-' Ff returns , and returns
EXPAN doesn’t carry out all possible expansions of an algebraic
in a single execution. Instead, EXPAN works clown through the
subexpression hierarchy, stopping in each brancli of the hierarchy
when it finds a subexpression that it can expand. It first examines
the top-level subexpression (the top level subexpression is the
algebraic itself). If it’s suitable for expansion, EXPAN expands
it and stops—otherwise, EXPAN examines all of the second-level
20-18 Calculus and Symbolic Manipulation