solve() problems

[HansB]

(06-06-2021 03:54 PM)Albert Chan Wrote:  You can quote the expression in CAS, to keep variable X "symbolic"

CAS> solve('X*X+X-1'=0, X)       → {1/2*(-√5-1), 1/2*(√5-1)}
CAS> proot('X*X+X-1')               → [−1.61803398875, 0.61803398875]

Thank you, works nicely! So solve() with expression in single quotes is quite useful, both in Home and in CAS, only CAS needs explicit mention of which var to solve, and never mind it is in upper case!

C.Ret Wrote:[....]
The program convert your sophisticated expression by replacing lowercase x with uppercase X without evaluating it and store it in the F1 ... F0 slot of you chose ready to be plot !
[....]

Thank you, your CAS2FUN program works beautiful, especially as it can place the expression into a Fn var of Function, and it gets instantly plotted there!

How do I write a reverse function, say FUN2CAS(n), which takes Fn from Function and inserts it into the CAS, with upper X replaced by lower x?