Question

if Z=3+5i, then Z3+Z+198=

Answer 1

z=3+5i

z3=(3+5i)3

=33+3.32(5i)+3.3(5i)2+(5i)3

=27−125i+135i−225

=−225+27+(135−125)i

=−198+10i

∴z3+z+198

=−198+10i+3+5i+198

=3+15i

Answer 2

z=3+5i

z ³ =(3+5i)³

=3³ +3.3² (5i)+3.3(5i)²+(5i)³

=27−125i+135i−225

=−225+27+(135−125)i

=−198+10i

∴z³ +z+198

=−198+10i+3+5i+198

=3+15i