Consider the following statements for a counter clockwise Nyquist path. 1. For a stable closed loop system,

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Consider the following statements for a counter clockwise Nyquist path.

1. For a stable closed loop system, the Nyquist plot of \(\mathrm{G}(s) \mathrm{H}(s)\) should encircle \((-1, j 0)\) point as many times as there are poles of \(\mathrm{G}(s) \mathrm{H}(s)\) in the right half of the \(s\) plane, the encirclements, if there are any must be made in the counter clockwise direction.

2. If the loop gain function \(\mathrm{G}(s) \mathrm{H}(\mathrm{s})\) is a stable function, the closed loop system is always stable.

3. If the loop gain function \(\mathrm{G}(s) \mathrm{H}(s)\) is a stable function, for a stable closed-loop system, the Nyquist plot of \(\mathrm{G}(s) \mathrm{H}(s)\) must not enclose the critical point ( \(-1, j 0\) ).

Which of the statements given above is/are correct?
(a) Only 1
(b) 1 and 2
(c) 1 and 3
(d) Only 3

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