POLYROOT

Polynomial roots. Returns the roots for the nth-order

 

polynomial with the specified n+1 coefficients.

 

 

POLYROOT([coefficients])

 

 

Example

 

 

For x4+2x3–25x2–26x+120:

 

 

POLYROOT([1,2,-25,-26,120]) returns

 

[2,-3,4,-5].

 

H I N T

The results of POLYROOT will often not be easily seen in

 

HOME due to the number of decimal places, especially if

 

they are complex numbers. It is better to store the results

 

of POLYROOT to a matrix.

 

 

For example, POLYROOT([1,0,0,-8]

M1 will

 

store the three complex cube roots of 8 to matrix M1 as

 

a complex vector. Then you can see them easily by going

to the Matrix Catalog. and access them individually in calculations by referring to M1(1), M1(2) etc.

Probability functions

COMB

Number of combinations (without regard to order) of n

 

things taken r at a time: n!/(r!(n-r)).

 

COMB(n, r)

 

Example

 

COMB(5,2) returns 10. That is, there are ten

 

different ways that five things can be combined two

 

at a time.!

 

Factorial of a positive integer. For non-integers, ! = Γ(x +

 

1). This calculates the gamma function.

 

value!

PERM

Number of permutations (with regard to order) of n things

 

taken r at a time: n!/(r!(n-r)!

 

PERM (n, r)

 

Example

 

PERM(5,2) returns 20. That is, there are 20

 

different permutations of five things taken two at a

 

time.

13-12

Using mathematical functions