Error Bad guess(es) on Hp 50g

Question

Hi,
when i try to use solve complex numbers on solve equation this msg is show to me 'error bad guess(es) 
one example is...
'y = G+B*i'
the 'i'  is the imaginary number (B ) and the real number is G 
so i put on solve equantion G  = 5  and  B = 0,003 and try to solve 'Y', i try a loot of things but the same msg of error is show to me, i dont know if i need to mark some flags  to do this work... help me please

Answer 1

Hi,
The numeric solver has trouble with complex numbers.
Also a note, the 50g uses complex numbers as a ordered pair (X;Y) where in rectangular mode X=real part and Y=imaginary part, in polar mode it is (r;theta) with an angle symbol before the theta.
You can use complex numbers in variables, so you can store the value of B as (0;0,003) and use the equation Y=G+B instead of Y=G+B*i.
to get a solution:
You can use EVAL to get the answer. Store the values in the required variables (5 in G and (0;0,003) in B), except the one to be solved for.
Then use EVAL,
e.g. EVAL(Y=G+B)
or on the RPN stack:
1:    Y=G+B
then press EVAL key.
for more comples equations, first solve for required variable using the symbolic solver, e.g.:
Y=2*G+B/3 and solve for G where Y=(5;0,5) and B=(3;0,5)
Use SOLVE (not SOLVEVX) from the symbolic solver menu:
SOLVE('Y=2*G+B/3','G')
or on the RPN stack:
2:    Y=2*G+B/3
1:    G
then select SOLVE from symbolic solver menu.
You will egt G=-(,166666666667*B-,5*Y)
Now store (5;0,5) in Y and (3;0,5) in B and use EVAL:
G=(2, ; ,166666666666)
Additional note: fraction mark set to , (comma). If fraction mark . (dot) is used the complex pair will show as ( X , Y ) and the last answer will show as G=(2. , .166666666666).
Note: I do not work for HP, I just like playing with calculators :-)