Texas Instruments TITANIUM TI-89 - Manual (Page 247)

Symbolic Manipulation 247
Delayed Simplification for Certain Built-In Functions Delayed Simplification for Certain Built-In Functions Delayed Simplification for Certain Built-In Functions Delayed Simplification for Certain Built-In Functions
Usually, variables are automatically simplified to their lowest possible level before they
are passed to a function. For certain functions, however, complete simplification is
delayed until after the function is performed.
Functions that Use Delayed Simplification Functions that Use Delayed Simplification Functions that Use Delayed Simplification Functions that Use Delayed Simplification
Functions that use delayed simplification have a required var argument that performs the
function with respect to a variable. These functions have at least two arguments with the
general form:
function(expression, var [, ... ] )
Note: Not all functions that use a var argument use delayed simplification.
For a function that uses delayed simplification:
1. The var variable is simplified to the lowest level at which it remains a variable (even if
it could be further simplified to a non-variable value).
2. The function is performed using the variable.
3. If var can be further simplified, that value is then substituted into the result.
For example: solve(x^2 N x N 2=0,x)
d(x^2 N x N 2,x)
‰ (x^2 N x N 2,x)
limit(x
2
N x N 2,x,5)