Maths problem-need help

[Bluedot]

Uh..this is not a typical mathematics forum, but I seriously need help with this.

(Image attached)

C'mon this is the section of all non-computer stuff...

Here 'z' is any complex number in the form z = x + iy

[Kazemagic]

more details pls...
i know that z-1 is not less than z-1+z but i dunno what does it mean by arg z...
Just replace z as a negative number..... but i dont know what do u mean by arg z...

[Bluedot]

'arg z' means argument of z, i.e if z = x + iy, then

arg z = tan^-1(y/x)

And this is a COMPLEX NUMBER problem.

[bonishah88]

if i'm not wrong |z|=squareroot(x^2 + y^2)

I did this a long time ago.

[MerleOne]

I think I would perform a change of variables, and write z=r*exp(i*theta)=r*cos(theta)+i*r*sin(theta), where theta is the argument and r the radius, then inject it in the formula and play with it a bit.