complex variables

Consider the following expression: z = sin(y + it) + cos(y $$-$$ it) where z, y, and t are variables, and $$i = \sqrt { - 1} $$ is a complex number. The partial differential equati...

Consider the following complex function $$f\left( z \right) = {9 \over {\left( {z - 1} \right)\left( {z + 2} \right)}}.$$ Which of the following is ONE of the residues of the above...

For an analytic function $$f\left( {x + i\,y} \right) = u\left( {x,y} \right) + i\,v\left( {x,y} \right),\,u$$ is given by $$u = 3{x^2} - 3{y^2}.$$ The expression for $$v,$$ consid...

The analytical function has singularities at, where $$f(z) = {{z - 1} \over {{z^2} + 1}}$$

Potential function $$\phi $$ is given as $$\phi \, = \,{x^2}\, - \,{y^2}$$. What will be the stream function $$\psi $$ with the condition $$\psi \, = \,0$$ at x = 0, y = 0?

Consider likely applicability of Cauchy's Integral theorem to evaluate the following integral counterclockwise around the unit circle C. $$I\, = \,\oint\limits_C {\sec z\,dz} $$, z...

$${e^z}$$ is a periodic with a period of