[Bug]-Missing root in solving equation

[pvp100288840]

(03-03-2019 02:28 AM)Helge Gabert Wrote:  You mean (x^2+x-1)^(x+3)=1, right?

The general solve() routine does indeed miss x=-1 as a valid root - - I suspect this is because the function returns complex results in the interval from around x=-1.618 ... to x=.618 ..., and only at x=-1 does the function disappear. (There is also a real result at x=0).

Of course fsolve() does not miss -1, given a suitable starting value, e.g., if you suspect a root at -1, you can always try

fsolve((x^2+x-1)^(x+3)=1, x=-1.1) returns -1.

Thanks a lot! But all TI calculators can solve this correctly(like TI-89).I wonder if it means that HP's(and also CASIO's) CAS algorithm do worse than TI?
Besides,How can I compare the CAS algorithm?