The open loop transfer function of a unity gain negative feedback control system is given by $G(s)=\frac{s^2+4s+8}{s(s+2)(s+8)}.$ The angle $\theta$ , at which the root locus approaches the zeros of the system, satisfies
- $|\theta|=\pi-\tan^{-1}[\frac{1}{4}]$
- $|\theta|=\frac{3\pi}{4}-\tan^{-1}[\frac{1}{3}]$
- $|\theta|=\frac{\pi}{2}-\tan^{-1}[\frac{1}{4}]$
- $|\theta|=\frac{\pi}{4}-\tan^{-1}[\frac{1}{3}]$