Question

z分之1=3+4i分之1 + 1+2i分之1 求z

Answer 1

1/z=1/(3+4i) + 1/(1+2i)

1/z=(3-4i)/(9+16)+(1-2i)/(1+4)

1/z=3/25-4i/25+1/5-2i/5

1/z=8/25-14i/25

z=1/(8/25-14i/25)

=2/25*/(4-7i)

=2/25*(4+7i) /(4-7i) (4+7i)

=2/25*(4+7i) /(16+49)

=2/25*(4+7i)/65

=8/1625+14/1625i