# The characteristic equation for a closed loop system with forward gain K is s4 + 4s3 + 8s2 + 6s + K = 0.

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The characteristic equation for a closed loop system with forward gain K is s4 + 4s3 + 8s2 + 6s + K = 0. The critical gain value Kc for stability should not exceed

(a) 3.25 (b) 9.75 (c) 13.0 (d) 23.3

The characteristic equation for a closed loop system with forward gain K is s4 + 4s3 + 8s2 + 6s + K = 0. The critical gain value Kc for stability should not exceed

(a) 3.25 (b) 9.75 (c) 13.0 (d) 23.3

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