HP 40gs HP 39gs_40gs_Mastering The Graphing Calculator_English_E_F2224-90010.p - Page 106

Solving for a missing value, The INFO report, the value you're trying to find

Page 106 highlights

Suppose you had the problem: "What acceleration is needed to increase the speed of a car from 16 ⋅ 67 m/s (60kph or ~38mph) to 27 ⋅ 78 m/s (100kph or 60mph) in a distance of 100m (~110 yd)?" We'll assume that you have already entered the equation into E2 (as above) and have made sure that it is ed. Solving for a missing value If you press NUM to change to the NUM view, you will see something similar to the screen on the right. What values are showing on your screen will depend on what happens to be in the memories V, U, A and D at the time. Pressing SHIFT CLEAR will zero all values. Move the highlight to V and enter the value 27 ⋅ 78 , then to U and enter 16 ⋅ 67 and finally to D and enter 100. Now move the highlight back to A (the value you're trying to find) and press the button. You should find that you obtain the answer to our problem of 2 ⋅ 47 m/s2. The INFO report When the process has finished, you can obtain a report on it by pressing the button. The result in this case may not seem very informative but there is more about these messages on page 106. The information they supply can be critical and you should develop the habit of checking them. 106

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Solving for a missing value
The INFO report
Suppose you had the problem:
“What acceleration is needed to increase the speed of a car from
16 67
m/s (60kph
or ~38mph) to
27 78
m/s (100kph or 60mph) in a distance of 100m (~110 yd)?”
E2
ed.
We’ll assume that you have already entered the equation into
(as above) and have made sure that it is
If you press
NUM
to change to the
NUM
view, you will see something
similar to the screen on the right.
What values are showing on your
screen will depend on what happens to be in the memories
V
,
U
,
A
and
D
at the time. Pressing
SHIFT CLEAR
will zero all values.
Move the highlight to
V
and enter the value
27 78
, then to
U
and enter
16 67
and finally to
D
and enter
100.
Now move the highlight back to
A
(the value you’re trying to find) and
press the
button. You should find that you obtain the answer to
our problem of
2 47
m/s
2
.
process has finished, you can obtain a report on it by
pressing the
When the
button. The result in this case may not seem very
informative but there is more about these messages on page 106.
The
information they supply can be critical and you should develop the habit
of checking them.
106