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[Bug]-Missing root in solving equation
03-03-2019, 02:28 AM
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RE: [Bug]-Missing root in solving equation
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.
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RE: [Bug]-Missing root in solving equation - Helge Gabert - 03-03-2019 02:28 AM



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