Symbolic functions

 

The symbolic functions are used for symbolic

 

manipulations of expressions. The variables can be

 

formal or numeric, but the result is usually in symbolic

 

form (not a number). You will find the symbols for the

 

symbolic functions = and (where) in the CHARS menu

 

(

CHARS) as well as the MATH menu.

= (equals)

Sets an equality for an equation. This is not a logical

 

operator and does not store values. (See “Test functions”

 

on page 11-18.)

 

 

expression1=expression2

ISOLATE

Isolates the first occurrence of variable in expression=0

 

and returns a new expression, where

 

variable=newexpression. The result is a general solution

 

that represents multiple solutions by including the (formal)

 

variables S1 to represent any sign and n1 to represent

 

any integer.

 

 

ISOLATE(expression, variable)

 

Examples

 

 

ISOLATE(2*X+8,X) returns -4

 

 

ISOLATE(A+B*X/C,X) returns -(A*C/B)

LINEAR?

Tests whether expression is linear for the specified

 

variable. Returns 0 (false) or 1 (true).

 

 

LINEAR?(expression, variable)

 

Example

 

 

LINEAR?((X^2-1)/(X+1),X) returns 0

QUAD

Solves quadratic expression=0 for variable and returns

 

a new expression, where variable=newexpression. The

 

result is a general solution that represents both positive

and negative solutions by including the formal variable S1 to represent any sign: + or – .

QUAD(expression, variable)

Example

QUAD((X-1)2-7,X) returns (2+s1*5.29150262213)/2

Using mathematical functions

11-17