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

If $z = x+iy$ and $w = \dfrac{(1-iz)}{(z-i)}$, then $|w| = 1$ implies that, in the complex plane

দৃশ্যকল্প ১: $\mathrm{z}=2+4 \mathrm{i}-\mathrm{i}^{2}$

দৃশ্যকল্প ২: $p x^{2}+q x+r=0$

If $z_1+ z_2 + z_3 = 0$ and $|z_1|=|z_2|=|z_3|= 1$, then area of triangle whose vertices are $z_1, z_2$ and $z_3$ is: