Which term of the sequence `12+8i ,\ 11+6i ,\ 10+4i ,...` is (a) purely real and (b). purely imaginary?

Which term of the sequence 8-6i ,7-4i ,6-2i ,..... is (i) purely real (ii) purely imaginary?

Which term of the sequence 12+8i,11+6i,10+4i,cdots is a purely real b.purely imaginary?

Which term of the sequence 8-6i,7-4i,6-2i,...... is (i) purely real (ii) purely imaginary?

Which term of the A.P. (16-6i,)(15-4i), (14-2 i), ... is a : (a) pure real number ? (b) pure imaginary number ?

Which term of the A.P. (16-6i,)(15-4i), (14-2 i), ... is a : (a) pure real number ? (b) pure imaginary number ?

Which term of the sequence : 8-6i, 7 - 4i, 6- 2i,.......... is pure imaginary ?

Which term of the sequence: 16-6i, 15-4i,14-2i ………. Is pure imaginary?

Which term of the sequences 8-6i, 7-4i, 6-2i, …………….is a real number?

If a and b are complex and one of the roots of the equation x^(2) + ax + b =0 is purely real whereas the other is purely imaginary, then

If a and b are complex and one of the roots of the equation x^(2) + ax + b =0 is purely real whereas the other is purely imaginary, then