HP 50g HP 50g_user's manual_English_HDPSG49AEM8.pdf - Page 82

The PROOT function, The QUOT and REMAINDER functions, Fractions

Page 82 highlights

The PROOT function Given an array containing the coefficients of a polynomial, in decreasing order, the function PROOT provides the roots of the polynomial. Example, from X2+5X+6 =0, PROOT([1, -5, 6]) = [2. 3.]. The QUOT and REMAINDER functions The functions QUOT and REMAINDER provide, respectively, the quotient Q(X) and the remainder R(X), resulting from dividing two polynomials, P1(X) and P2(X). In other words, they provide the values of Q(X) and R(X) from P1(X)/P2(X) = Q(X) + R(X)/P2(X). For example, QUOT('X^3-2*X+2', 'X-1') = 'X^2+X-1' REMAINDER('X^3-2*X+2', 'X-1') = 1. Thus, we can write: (X3-2X+2)/(X-1) = X2+X-1 + 1/(X-1). NOTE: you could get the latter result by using PARTFRAC: PARTFRAC('(X^3-2*X+2)/(X-1)') = 'X^2+X-1 + 1/(X-1)'. The PEVAL function The function PEVAL (Polynomial EVALuation) can be used to evaluate a polynomial p(x) = an⋅xn+an-1⋅x n-1+ ...+ a2⋅x2+a1⋅x+ a0, given an array of coefficients [an, an-1, ... a2, a1, a0] and a value of x0. The result is the evaluation p(x0). Function PEVAL is not available in the ARITHMETIC menu, instead use the CALC/DERIV&INTEG Menu. Example: PEVAL([1,5,6,1],5) = 281. Additional applications of polynomial functions are presented in Chapter 5 in the calculator's user's guide. Fractions Fractions can be expanded and factored by using functions EXPAND and FACTOR, from the ALG menu (,×). For example: EXPAND('(1+X)^3/((X-1)*(X+3))')='(X^3+3*X^2+3*X+1)/(X^2+2*X-3)' EXPAND('(X^2)*(X+Y)/(2*X-X^2)^2)')='(X+Y)/(X^2-4*X+4)' FACTOR('(3*X^3-2*X^2)/(X^2-5*X+6)')='X^2*(3*X-2)/((X-2)*(X-3))' Page 5-9

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Page 5-9
The PROOT function
Given an array containing the coefficients of a polynomial, in decreasing
order, the function PROOT provides the roots of the polynomial.
Example,
from X
2
+5X+6 =0, PROOT([1, –5, 6]) = [2. 3.].
The QUOT and REMAINDER functions
The functions QUOT and REMAINDER provide, respectively, the quotient
Q(X) and the remainder R(X), resulting from dividing two polynomials,
P
1
(X) and P
2
(X).
In other words, they provide the values of Q(X) and R(X)
from P
1
(X)/P
2
(X) = Q(X) + R(X)/P
2
(X).
For example,
QUOT(‘X^3-2*X+2’, ‘X-1’) = ‘X^2+X-1’
REMAINDER(‘X^3-2*X+2’, ‘X-1’) = 1.
Thus, we can write: (X
3
-2X+2)/(X-1) = X
2
+X-1 + 1/(X-1).
The PEVAL function
The function PEVAL (Polynomial EVALuation) can be used to evaluate a
polynomial
p(x) = a
n
x
n
+a
n-1
x
n-1
+ …+ a
2
x
2
+a
1
x+ a
0
,
given an array of coefficients [
a
n
, a
n-1
, … a
2
, a
1
, a
0
] and a value of
x
0
.
The result is the evaluation
p(x
0
).
Function PEVAL is not available in the
ARITHMETIC menu, instead use the CALC/DERIV&INTEG Menu.
Example:
PEVAL([1,5,6,1],5) = 281.
Additional applications of polynomial functions are presented in Chapter 5
in the calculator’s user’s guide.
Fractions
Fractions can be expanded and factored by using functions EXPAND and
FACTOR, from the ALG menu (
‚×
).
For example:
EXPAND(‘(1+X)^3/((X-1)*(X+3))’)=‘(X^3+3*X^2+3*X+1)/(X^2+2*X-3)’
EXPAND(‘(X^2)*(X+Y)/(2*X-X^2)^2)’)=‘(X+Y)/(X^2-4*X+4)’
FACTOR(‘(3*X^3-2*X^2)/(X^2-5*X+6)’)=‘X^2*(3*X-2)/((X-2)*(X-3))’
NOTE
: you could get the latter result by using PARTFRAC:
PARTFRAC(‘(X^3-2*X+2)/(X-1)’) = ‘X^2+X-1 + 1/(X-1)’.