Is this transfer function unstabile?(adsbygoogle = window.adsbygoogle || []).push({});

Spoiler: This is a feedback control system related issue

I am trying to sketch the bode plot of the following transfer function but I can't find a solution.

I should use 20log( unknown / 3 * 10) to find where the magnitude starts.

G(s) = (s^2+4s+25) / ((s+3)*(s+10))

It is very appealing to solve the second grade equation, which give complex solutions.

http://www.wolframalpha.com/input/?i=bode+plot+(s^2+4s+25)/((s+3)(s+10)

Question 1) Is the system unstable because the poles/zeros are on the right side?

Question 2) What should I do with the second grade equation to find the values I need to sketch the bode plot?

Question 3) Does it have 3 break frequencies?

What I'm looking for is something that looks like, i.e. ((s+923) / ((s+3)*(s+20))),

so that I have 3 break frequencies and initial magnitude of 20log(923/(3*20)

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# Is this transfer function unstable?

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