If the conjugate of $(x+iy)(1-2i)$ is $(1+i)$,then

If $\bar{z}$ is the conjugate of the complex number $z$,then which of the following relations is false?

Let $z$ be a complex number such that $|z|+z=2+i$,where $i=\sqrt{-1}$. Then $|z|$ is equal to:

What is the modulus of the complex number $(1+2i)(-2+i)$?

If $x + iy = \sqrt{\frac{a + ib}{c + id}}$,then $(x^2 + y^2)^2 = $

If ${z_1}, {z_2}, {z_3}$ are complex numbers such that $|{z_1}| = |{z_2}| = |{z_3}| = \left| \frac{1}{z_1} + \frac{1}{z_2} + \frac{1}{z_3} \right| = 1$,then $|{z_1} + {z_2} + {z_3}|$ is