Mathematician Finds Easier Way to Solve Quadratic Equations

[Albert Chan]

(05-08-2024 02:23 AM)Gerson W. Barbosa Wrote:  I assume by KISS you mean “Keep It Simple & Short”. Anyway, for me the acronym would sound offensive only if there were a comma before the second S (“Keep it simple stupid” is quite a different thing than “keep it simple, stupid!”– at least for those of us who use to place a comma before nouns in vocative case).

KISS principle have many variations, not necessarily end in Stupid.
Comma or not, Stupid is meant as a tease, not in a negative way!

Quote:relational < operator doesn’t work for complex numbers on the HP-42S.

I was comparing absolute value, going for the big root.
This is *exactly* the same as your cos/asin trig formula.

(05-04-2024 07:37 PM)Gerson W. Barbosa Wrote:  \(x_{1}=\left({\cos\left({\arcsin{\frac{\sqrt{q}}{-\frac{p}{2}}}}\right)+1}\right)\times-\frac{p}{2}\)

Replace cos(asin(z)) = √(1-z²), we have KISS version, only 1 square root!

Code:

00 { 28-Byte Prgm }
01▸LBL "Q"
02 X<> ST Z         ;   a   b   c
03 STO÷ ST Z        
04 STO+ ST X
05 +/-              
06 ÷                ;   m   q
07 ENTER            
08 X↑2              ; m^2   m   q
09 RCL- ST Z        ; m^2-q m   q
10 RCL÷ ST L
11 SQRT
12 RCL× ST Y        
13 +                ; x1    q
14 STO÷ ST Y        ; x1    x2
15 END