If z1=2−i and z2=1+i, find ∣∣z1+z2+1z1−z2+1∣∣
Here z1=2−i and z2=1+i
∴ ∣∣z1+z2+1z1−z2+1∣∣
=∣∣2−i+1+i+12−i−1−i+1∣∣=∣∣42−2i∣∣
=∣∣42−2i∣∣=4√(2)2+(−2)2
=4√4+4=4√8=42√2=√2
If z+x+iy then (z)=√x2+y2 z1=2−i,z2=1+i, find ∣∣z1+z2+1z1−z2+i∣∣.