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Consider the following statements :

(a) \(|e^{\sin z}|\) does not assume its maximum value in C.
(b) \(|\sin(e^{z})|\) does not assume its minimum value in C.

Then :

  • A.Only (a) is true
  • B.Only (b) is true
  • C.Both (a) and (b) are true
  • D.Both (a) and (b) are false

Answer: A

Only (a) is true.

(a) \(e^{\sin z}\) is a non-constant entire function, so by the maximum modulus principle its modulus has no maximum on C; indeed it is unbounded.

(b) is false. \(\sin(e^{z})\) has zeros: \(e^{z} = \pi\) has the solution \(z = \ln \pi\), and \(\sin \pi = 0\). So \(|\sin(e^{z})|\) attains its minimum value 0. The minimum modulus principle forbids an interior minimum only for functions without zeros.

So 'only (b)', 'both true' and 'both false' are wrong.

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