4-66 Computer Algebra Commands
3
⋅()
7
⋅()+
SIN 5 X⋅()
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Input: An algebraic expression.
Output: A list containing, the points where the expression changes sign, and between each pair of
points, the sign of the expression between those points.
Flags: Exact mode must be set (flag –105 clear).
Numeric mode must not be set (flag -3 clear).
Radians mode must be set (flag –17 set).
Example: Show the ranges of values of x for which the expression 2-x
2
is positive and negative.
Command:
SIGNTAB(2 – X^2)
Result: { '-∞' – '-√2' + '√2' – '+∞' }
See also: TABVAR
SIMP2
Type: Command
Description: Simplifies two objects by dividing them by their greatest common divisor.
Access: Arithmetic, !Þ L
Input: Level 2/Argument 1: The first object.
Level 1/Argument 2: The second object.
Output: Level 2/Item 1: The first object divided by the greatest common divisor.
Level 1/Item 2: The second object divided by the greatest common divisor.
Flags: Exact mode must be set (flag –105 clear).
Numeric mode must not be set (flag -3 clear).
Radians mode must be set (flag –17 set).
Example: Divide the following expressions by their greatest common divisor:
x
3
6x
2
11x 6+++
x
3
7x–6–
Command: SIMP2(X^3+6*X^2+11*X+6, X^3-7*X-6)
Result: {X+3,X-3}
See also: EGCD
SIMPLIFY
Type: Command
Description: Simplifies an expression.
Access: !Ú REWRITE L
Input: An expression
Output: An equivalent simplified expression. SIMPLIFY follows an extensive built-in set of rules, but
these might not give exactly the simplification the user expects.
Flags: Exact mode must be set (flag –105 clear).
Numeric mode must not be set (flag -3 clear).
Example: Simplify
Command: SIMPLIFY((SIN(3*X)+SIN(7*X))/SIN(5*X))
Result: 4*COS(X)^2 - 2
See also: COLLECT, EXPAND