Using mathematical functions 13-11
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,C
2
) returns 55.
Matrix functions
These functions are for matrix data stored in matrix 
variables. See “Matrix functions and commands” on 
page 15-10.
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 x
4
+2x
3
–25x
2
–26x+120.
POLYEVAL Polynomial evaluation. Evaluates a polynomial with the 
specified coefficients for the value of x.
POLYEVAL([coefficients], value)
Example
For x
4
+2x
3
–25x
2
–26x+120: 
POLYEVAL([1,2,-25,-26,120],8) returns 
3432.
POLYFORM Polynomial form. Creates a polynomial in variable1 from 
expression. 
POLYFORM(expression, variable1) 
Example
POLYFORM((X+1)^2+1,X) returns X^2+2*X+2.
HP 39gs English.book  Page 11  Wednesday, December 7, 2005  11:24 PM