Solver bug for secondary roots?
Posted: Wed Aug 29, 2018 2:44 am
While waiting for my DM42 to arrive (it's a long way from Switzerland to Canada!) I've been refreshing my memory of the HP-42S by playing with the Free42 program on my Linux box.
I've tried using the Solver on the following program for (x - 7)(x - 11) = 0 :
This should have roots 7 and 11. My problem is getting the second root x=11 by entering initial estimates of 9 and 20, using the procedure described in the HP-42S Owner's Manual, Chapter 12, section "Choosing Initial Guesses". I entered the following keys:
(Shift) (Solve) (Soft key for QUAD)
OK, now I'm in the solver for program QUAD. More keys:
(9) (Soft key for X)
which should store the low estimate for X. Now to store the high estimate:
(2) (0) (Soft key for X)
To solve for X:
(Soft key for X)
I get answer "X=9.0000" which is clearly not correct (should be 11). Did I do something wrong?
I'm using Free42 2.0.21 on Linux amd64 (Debian 9.4.0).
I've tried using the Solver on the following program for (x - 7)(x - 11) = 0 :
Code: Select all
00 { 25-byte Prgm }
01 LBL "QUAD"
02 MVAR "X"
03 RCL "X"
04 ENTER
05 7
06 -
07 X<>Y
08 11
09 -
10 x
11 .END.
(Shift) (Solve) (Soft key for QUAD)
OK, now I'm in the solver for program QUAD. More keys:
(9) (Soft key for X)
which should store the low estimate for X. Now to store the high estimate:
(2) (0) (Soft key for X)
To solve for X:
(Soft key for X)
I get answer "X=9.0000" which is clearly not correct (should be 11). Did I do something wrong?
I'm using Free42 2.0.21 on Linux amd64 (Debian 9.4.0).