Radio Shack TRS-80 PC-3 Owner's Manual page 239

INSTRUCTIONS
INPUT
Starting point
Minute interval
Interval
y
---f---+---.,f-\--+-v-t-+l*:--t----+
x
I nterval width
OUTPUTS
Starting point
Root value (by pressing the
(ENTER)
key, the next interval's root is found)
EXAMPLE
x
3
-
2x
2
- X
+ 2 = 0 (the roots are -1,1,2)
starting point
=
0
minute interval
=
10-
4
interval
=
0.5
The above values are used in the calculation.
The functions are to be written into lines after 500 as subroutines.
How to type in the example:
1. Go into PRO mode by operating the mode change key.
2. 500B
=
((X-2)
*
X-1)
*
X+2
(ENTER)
510 RETU RN
(ENTER)
That is all that has to be done.
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