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Why when I plot diagram of Bode G(s)=4 (s-20)/(s (s+0.8)), it does not recognize that the constant gain is negative and should be started from -180 degree phase, while Methematica starts to + 0 Degree ? There is a problem in PhasePlot. Anyone can...

DSolve[{k \!\( \*SubscriptBox[\(\[PartialD]\), \(r\)]\((r\ \*SubscriptBox[\(\[PartialD]\), \(r\)]T[r])\)\) == 0, T[a] == T0, -k T'[b] == qo} , T[r], r] // Simplify Marco I do not understand, how do the formatting symbol to...