Question

The modulus of the complex number $\left(\frac{3+4i}{1-2i}\right)$ is

• A. $5$
• B. $\sqrt{5}$
• C. $\frac{1}{\sqrt{5}}$
• D. $\frac{1}{5}$

Answer 1

The correct option is B $\sqrt{5}$

$\left|\frac{3+4i}{1-2i}\right|=\frac{\sqrt{9+16}}{\sqrt{1+4}}=\sqrt{5}$