Aptitude : : Complex Number Questions & Answers

  1. Find a and b, where a and b are real numbers so that a + ib = (2 - i)2

A. a = 4 and b = - 3

B. a = 3 and b = - 4

C. a = - 4 and b = 3

D. a = 3 and b = 4

  1. Compute real and imaginary part of $Z=\dfrac{\text{i}-4}{2\text{i}-3}$

A. Re(Z) = $\dfrac{14}{13}$ and Im(Z) = $\dfrac{5}{13}$

B. Re(Z) = $\dfrac{5}{13}$ and Im(Z) = $\dfrac{14}{13}$

C. Re(Z) = $\dfrac{5}{13}$ and Im(Z) = $\dfrac{5}{13}$

D. Re(Z) = $\dfrac{14}{13}$ and Im(Z) = $\dfrac{14}{13}$

  1. Simplify the given expression $\text{i}^3 + \text{i}^6 + \text{i}^9 $

A. 1

B. -1

C. i

D. - i

  1. Any integral power of i (iota) can be expressed as :

A. None of these

B. ± 1 or ± i

C. ± 1

D. ± i

  1. If z is a complex number, then z ⚹ z = 0 if and only if

A. z = 0

B. Re(z) = 0

C. Im(z) = 0

D. None of these