HP 40gs - Manual (Page 192)

14-10 Computer Algebra System (CAS)
For example, suppose you have stored the expression x 2
in G, and have defined the function F(x) as x 2 . Suppose
now you want to calculate INTVX(X 2 ). You could:
• enter INTVX(X 2 ) directly, or
• enter INTVX(G), or
• enter INTVX(F(X)).
Note that you can apply the command directly to an
expression or to a variable that holds an expression (the
first two cases above). But where you want to apply it to
a defined function, you need to specify the full function
name, F(X), as in the third case above.
ALGB menu
COLLECT Factors over the integers
COLLECT combines like terms and factors the expression
over the integers.
Example
To factor over the integers you would type:
COLLECT(X 2 –4)
which gives in real mode:
Example
To factor over the integers you would type:
COLLECT(X 2 –2)
which gives:
DEF Define a function
For its argument, DEF takes an equality between:
1. the name of a function (with parentheses containing
the variable), and
2. an expression defining the function.
DEF defines this function and returns the equality.
x
2
4 –
x 2 + ( ) x 2 – ( ) ⋅
x
2
2 –
x
2
2 –
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