HP 39g+, Руководство пользователя

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Using mathematical functions 11-11
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
.
POLYROOT
Polynomial roots. Returns the roots for the n th-order
polynomial with the specified n +1 coefficients .
POLYROOT
([ coefficients ])
Example
For
x
4
+2x
3
–25x
2
–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.