hp40g+.book Page 11 Friday, December 9, 2005 1:03 AM

RECURSE

Provides a method of defining a sequence without using

 

the Symbolic view of the Sequence aplet. If used with

 

(“where”), RECURSE will step through the evaluation.

 

RECURSE(sequencename, termn, term1, term2)

 

Example

 

 

RECURSE(U,U(N-1)*N,1,2)

U1(N)

 

Stores a factorial-calculating function named U1.

 

When you enter U1(5), for example, the function

 

calculates 5! (120).

 

Σ

Summation. Finds the sum of expression with respect to

variable from initialvalue to finalvalue. Σ(variable=initialvalue, finalvalue, expression)

Example

Σ(C=1,5,C2) returns 55.

Matrix functions

 

These functions are for matrix data stored in matrix

 

variables. See “Matrix functions and commands” on

 

page 18-10.

Polynomial functions

 

Polynomials are products of constants (coefficients) and

 

variables raised to powers (terms).

POLYCOEF

Polynomial coefficients. Returns the coefficients of the

 

polynomial with the specified roots.

 

POLYCOEF ([roots])

 

Example

 

To find the polynomial with roots 2, –3, 4, –5:

 

POLYCOEF([2,-3,4,-5]) returns[1,2,-25,

 

-26,120], representing x4+2x3–25x2–26x+120.

POLYEVAL

Polynomial evaluation. Evaluates a polynomial with the

 

specified coefficients for the value of x.

POLYEVAL([coefficients], value)

Using mathematical functions

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