Are the poles of the following transfer function correct?

Question

$ H(s) = \frac{M_2p}{M_1(M_1M_2s^4 + M_1ps^2 + M_2ps^2)}$

Poles : ${ s^2(M_1M_2s^2 + M_1p + M_2p)} = 0$

${ s ^2 = \frac{-p(M_1+M_2)}{(M_1M_2)}}$

${ s= \sqrt{\frac{-p(M_1+M_2)}{(M_1M_2)}}}$ and ${ s = 0}$

Answer 1

Yes, but if you want to list all poles, then you should also add,

$$ s = -\sqrt{\frac{-p(M_1+M_2)}{M_1\,M_2}} $$

and mention that $s=0$ has a multiplicity of two.