Z₁= -3i এবং  Z₂= 1+i 

$\frac{Z_{2}}{Z_{1}}$   এর পরমমান কত?

If $a, b, c, d$ be a form consecutive term of an increasing A.P., then the roots of the equation $\left( {x - a} \right)\left( {x - c} \right) + 2\left( {x - b} \right)\left( {x - d} \right) = 0$

$z = \frac{1 - i}{2 i}$  |z|=কত?

If ${z}_{1},{z}_{2},..{z}_{n}$ lie on the circle $|z|=2$ then the value of $|{z}_{1}+{z}_{2}+..{z}_{n}|-4|\dfrac {1}{{z}_{1}}+\dfrac {1}{{z}_{2}}++\dfrac {1}{{z}_{n}}|=$