MCQ
Mark the correct answer for: $i ^{-38}=$ ?
  • A
    i
  • B
    -i
  • C
    -1
  • D
    1

Answer

(c)-1
Explanation: $i ^{-38}=\frac{1}{i^{38}} \times \frac{i^2}{i^2}=\frac{-1}{i^{-40}}=\frac{-1}{\left(i^4\right)^{10}}=\frac{-1}{i^{10}}=\frac{-1}{1}=-1$

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