MCQ
Solve $x^2 + 1 = 0$.
- A$x = 1, -1$
- ✓$x = i, -i$
- C$x = -1$
- D$x = i$
✓
Answer
Correct option: B.
$x = i, -i$
$\text{x}^2 + 1 = 0$
$\Rightarrow\text{x}^2=-1$
$\Rightarrow\text{x}$
$=\pm\sqrt{-1}=\pm\text{i}$
$\Rightarrow\text{x}^2=-1$
$\Rightarrow\text{x}$
$=\pm\sqrt{-1}=\pm\text{i}$
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