HP 39GS hp 39gs_user's guide_English_E_HDPMG39AE13.pdf - Page 164

POLYROOT HINT 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]. 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 PERM 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! 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