The Fcn Menu; Root - HP 39g Master Manual

T h e F C N m e n u
T h e F C N m e n u
Before continuing, set the axes back to the way
we set them at the start of the section on the
Menu bar.
Looking at the menu functions again, you will see that the only one we have
not yet examined is the one labeled
Tools FCN menu.
Before you use this key, make sure
switched on and move the cursor so that it is in
roughly the position shown right.

Root

Press the key. As you can see on the
right, this key gives you access to a number of
useful tools. If you leave the highlight on Root
(as shown) and press ENTER (or
the cursor will jump to the nearest root or x
intercept for the function it is on, starting its
search at the current position. Try it now.
Notice the message at the bottom of the
screen giving the value of the root that was
found. To find the other root, you need to move
the cursor so that it is closer to the other root
than to the present one. In general that means
moving it past the turning point.
Calculator Tip
If you are working with a function which has asymptotes
then make sure the cursor is positioned on the same side
of the asymptote as the root. The internal algorithm used
does not seem to cope well with crossing asymptotes.
. This key pops up the Function
is
) then
63
Move to about
this position.