And then we say. So, this is again a simple polygon, because any point this can act as a boundary and. So, similarly I call this A infinity, I will take this point as A B as minus 1 and this distance is called as B as minus 1, I have C is 1, then I have D infinity and then
we say the fluid speed is hence in this these are the points you represent then what will happen to my d z by d zeta will be K. And that will give us B z 3 pi by 2 angle and B is minus 1. So, this is zeta plus 1 it is alpha by pi minus 1. So; that means, alpha is 3 pi by 2 pi by 2 3 by 2 minus 1 is half and this is this point is pi by 2. So, this will be zeta minus 1 to the power of minus half and the contribution from this end and this end will not come into picture. So, d z by d zeta is this so which you can write it as K zeta by zeta square minus 1 plus K by zeta square minus 1 root over.