$$ \text { Let } f(z)=x^{2}+a x y+b y^{2}+i\left(c x^{2}+d x y+y^{2}\right) \in A(Z \text { -plane }), \text { find } a, b, c, d \text { . } $$
If we put $$a=2,b=1,c=1,d=2$$ Then we get... $$f(z)=(x+y)^2(1+i)=X+iY$$
Is that what they want?
Can you please tell me ?? I have one more doubt related to it..but maybe after this it may get already cleared