HP 39g hp 39g+ (39g & 40g)_mastering the hp 39g+_English_E_F2224-90010.pdf - Page 91

Finding and accessing polynomial roots, POLYROOT, Matrix, Catalog

Page 91 highlights

Finding and accessing polynomial roots The POLYROOT function can be used to find roots very quickly, but the results are often difficult to see in the HOME view, particularly if they include complex roots. This can be dealt with easily by storing the results to a matrix. For example, suppose we want to find the roots of f (x) = x3 −3x2 + 3 . We will use the POLYROOT function and store the results into M1. The advantage of this is that you can now view the roots by changing to the Matrix Catalog. and pressing . See page 170 for more detailed information on matrices. In addition to this, you can access the roots in the HOME view as shown. Calculator Tip This trick is particularly helpful if you are working with complex roots. Not only does it make it easier to re-use them it makes it easier to tell at a glance which are real and which complex. 91

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91
Finding and accessing polynomial roots
The
POLYROOT
function can be used to find roots very quickly, but the results
are often difficult to see in the
HOME
view, particularly if they include complex
roots.
This can be dealt with easily by storing the results to a matrix.
For example, suppose we want to find the
roots of
3
2
()
3
3
fx
x
x
=
+
.
We will use the
POLYROOT
function and store the results into
M1
.
The advantage of this is that
you can now view the roots
by changing to the
Matrix
Catalog
. and pressing
.
See page 170 for more
detailed information on matrices.
In addition to this, you can access the roots in
the
HOME
view as shown.
Calculator Tip
This trick is particularly helpful if you are working with
complex roots. Not only does it make it easier to re-use
them it makes it easier to tell at a glance which are real
and which complex.