If BCD is semicircle arc in the plane of AB and DE with center at O and radius r and line DB makes angle a with a with DE then find the magnitude of magnetic induction produce at point O

WE know for  SEMIN INFINITE WIRE we have...therefore it is   ..  IT IS for one semi infinite wire for 2 semi infinite wire we have to multiply by 2 i.e........  Now   FOR SEMI CIRCLE IT IS  eqn (2)     on adding both the magnetic field we get ….      …....  since