lf |z1|=2, |z2|=3, then |z1+z2+5+12i| is less than or equal to
if z1,z2 and z3 are complex numbers such that
|z1|=|z2|=|z3|=∣∣1z1+1z2+1z3∣∣=1,
then |z1+z2+z3|