None of the coefficients can be zero or negative unless one of the following occurs:
A. One or more roots have positive real parts
B. A root at origin
C. Presence of root at the imaginary axis
D. All of the mentioned
Answer:D
None of the coefficients can be zero or negative unless one of the following occurs:
A. One or more roots have positive real parts B. A root at origin C. Presence of root at the imaginary axis D. All of the mentioned
Explanation: None of the coefficients can be zero or negative unless one or more roots have positive real parts, root at origin and presence of root at the imaginary axis.