Find the roots $n$ how many broots get from the equation

Question

Calculate the number of roots of $s^4+2s^2+1=0$ on right half,left half and imaginary axis of S-plane.

Answer 1

Assuming the $S$-plane is just $\Bbb C$:

$$s^4 + 2s^2 + 1= (s^2 + 1)^2 = 0$$

so the complex solutions are $i$ and $-i$, both with multiplicity $2$. Draw your conclusions.