4-58 Computer Algebra Commands
Description: Rewrites an expression raised to a power as a product. If followed by repeated execution of
DISTRIB allows an expression to be expanded fully, step by step.
Access: !Ú REWRITE L
Input: An expression raised to a power.
Output: The result from applying the distributive property of exponentiation over multiplication.
Flags: Exact mode must be set (flag –105 clear).
Numeric mode must not be set (flag -3 clear).
Example: Expand (X+1)
3
.
Command: POWEXPAND((X+1)^3)
Result: (X+1)⋅(X+1)⋅(X+1)
POWMOD
Type: Function
Description: Raises an object (number or expression) to the specified power, and expresses the result
modulo the current modulus.
Access: Arithmetic,
!Þ MODULO L
Input: Level 2/Argument 1: The object.
Level 1/Argument 2: The exponent.
Output: The result of the object raised to the exponent, modulo the current modulus.
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).
PREVAL
Type: Function
Description: With respect to the current default variable, returns the difference between the values of a
function at two specified values of the variable.
PREVAL can be used in conjunction with INTVX to evaluate definite integrals. See the
example below.
Access: Calculus, !Ö
DERIV. & INTEG L.
Input: Level 3/Argument 1: A function.
Level 2/Argument 2: The lower bound.
Level 3/Argument 1: The upper bound.
The bounds can be expressions.
Output: The result of the evaluation.
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: Evaluate the following:
x
3
3x+()xd
0
3
∫
Command: PREVAL(INTVX(X^3+3*X),0,3)
Result: 135/4
PREVPRIME
Type: Function