Q. z 1 and z 2 are two complex numbers such that z 1 - 2 z 2 2 - z 1 z 2 ¯ is unimodular whereas z 2 is not a unimodular. Then | z 1 | is 1 2 3 4 Share with your friends Share 13 Neha Sethi answered this Dear student A complex number z is said to be unimodular if |z|=1.Consider, z1-2z22-z1z2Since z1-2z22-z1z2 is unimodular then z1-2z22-z1z2=1⇒|z1-2z2|=|2-z1z2|⇒|z1-2z2|2=|2-z1z2|2⇒z1-2z2z1-2z2=2-z1z22-z1z2 using z2=zz⇒z1z1-2z1z2-2z2z1+4z2z2=4-2z1z2-2z1z2+z1z1 z2z2⇒z12+4z22=4+z12z22⇒z12+4z22-4-z12z22=0⇒z121-z22-41-z22=0⇒1-z22z12-4=0Since z2≠1⇒z12-4=0⇒z12=4⇒z1=2 Regards 24 View Full Answer