If a is a complex number such that `|a|=1`, then find thevalue of a, so that equation `az^2 + z +1=0` has one purely imaginary root.

If roots of the equation z^(2)+az+b=0 are purely imaginary then

If a cos alpha+i sin alpha and the equation az^(2)+z+1=0 has a pure imaginary root, then tan alpha=

If a,b,c are non-zero real numbers and the equation ax^(2)+bx+c+i=0 has purely imaginary roots,then

Consider the quadratic equation az^(2)+bz+c=0 where a,b,c are non-zero complex numbers. Now answer the following. The condition that the equation has both roots purely imaginary is

If a complex number Z is purely imaginary then conjugate of Z is

If a complex number Z is purely imaginary then conjugate of Z is