Which term of the series (28-16i) + (27-14i) + (26-12i) +….is purely real.

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

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

Find theta such that (3+2i sin theta)/(1-2i sin theta) is purely real.

Find the real part of (1-i)^(-i) .

Find the least positive integral value of n, for which ((1-i)/(1+i))^n , where i=sqrt(-1), is purely imaginary with positive imaginary part.

Find the square roots of - 48-14i .

If z = x + iy and w=(1-iz)/(z-i) , show that : |w|=1 implies z is purely real.

Find the sum of n terms of the series whose nth terms is (i) n(n-1)(n+1) .

Which term of sequence 36, 31, 26, 21, 16... is the first negative term ?

Solve ix^2 - x + 12i= 0 .