HP 39gs_40gs_Mastering The Graphing Calculator_English_E_F2224-90010

Example 9: Investigation of a complex function
()
=
1
z
2
+ z in parametric form and graph it. Show
Rewrite the function
f
z
2
π
⎛⎞
that it is symmetrical about the x axis and evaluate
f
⎜⎟
as an exact surd.
3
⎝⎠
i. The first step is to enter the function.
1 2 ALPHA Z
ALPHA Z
⋅
ii. We now transform it into exponential form by using the
SUBST function to replace z with e
it
.
SHIFT ENTER
ALPHA Z SHIFT = SHIFT
e
x
SHIFT i SHIFT ALPHA t
SHIFT
ENTER
Note: The reason for pressing
within the menu
is to jump to the first function starting with an
S, the letter on the
key. Pressing it again jumps to the next function starting
with
S, which is SUBST.
iii. Next we linearize it…
ENTER ENTER ENTER
Note: 1. As in the previous case, the
is used
to jump to the first function that starts with
an
L, the letter on .
2. The hp 40gs will probably ask if it should
turn “Complex mode” on, assuming it is in
its default configuration. One of the
ENTERs
is to tell it “Yes”.
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