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I have the following question
I need to Draw the Bode Plot,so i need to find Magnitude and Phase Angles for a Frquency.I understand that i need to susbstitude S=jW(W>Omega) as per this video
https://www.youtube.com/watch?v=8cwczVhTKiE
But in my question that denominator is not of the from (1+xxS)(1+XXS) so how should i proceed.Please advice.
"denominator is not of the from (1+xxS)(1+XXS)"
If you like such a form (and I would agree with you for solving the present task), you have nothing to do than to find the complex roots (s1 and s2) of the denominator equation D(s)=0. Then you can write D(s)=(1-s1)(1-s2).
EDIT: Regarding the three other questions - I have some problems to understand the meaning. Stability parameters are defined for systems with feedback only. For all stability calculations we need the loop gain. Here, we have a given transfer function - and that´s all we have. Hence, these three questions make no sense, unless a feedback loop is shown.
Look at it like this: -
\$s^2+ s + 1\$ becomes \$1-\omega^2 +j\omega\$
In other words you have a real and imaginery part. I've just substituted s with jw remembering that \$j^2\$ = -1.
Multiply numerator and denominator by the complex conjugate (\$1-\omega^2 -j\omega\$) to bring all the terms of j to the numerator. Denominator becomes \$(1-\omega^2)^2 +\omega^2\$ and as you can see there are no "j" terms.
Is this enough of a hint to get you to a solution?
