10th Class Mathematics Chapter 1 Test01. Complex Numbers

Q1. Multiple choice questions (Attempt all · 8 × 1 = 8)

1. $\frac{2}{1 - i}$ =?
   1. $\frac{1 + i}{2}$
   2. $\frac{(1+i)^2}{2}$
   3. $1 - i$
   4. $1 + i$
2. $1 + (i)^9$ = ?
   1. $1 + i$
   2. $1 +\sqrt{-1}$
   3. $1 - i$
   4. $-i$
3. $(-xi)19$ = ?
   1. $-x^{19}i$
   2. $x^{19}i$
   3. $-i^{19}$
   4. $-x^{19}$
4. Conjugate of $\sqrt{x} - i\sqrt{y}$ is:
   1. $\sqrt{x} + i\sqrt{y}$
   2. x - y
   3. x - y
   4. x + y
5. If $z = x + iy$ , then z $\bar{z}$ is.
   1. Imaginary
   2. Complex
   3. Non-negative number
   4. Negative number
6. If $x < o$ then $\sqrt{x}$ is :
   1. Real
   2. Complex
   3. Irrational
   4. Rational
7. The solution of $x^2 + 4 = 0$ is:
   1. $2i$
   2. $-2i$
   3. $± 2i$
   4. ± 2
8. $\sqrt{-25} + \sqrt[3]{8}$ is equal to:
   1. $-5 +\sqrt[3]{8}$
   2. $2 + 5i$
   3. $-5 +2i$
   4. $2\sqrt{2} +5i$