Qn 4. If a function f(2) is holomorphic in a domain, does it imply that f(z) is also holomorphic in that domain? Give reasons for your answer. If f(z) and f(z) are both holomorphic in a domain D, what can be said about f(z) in D? [5, 3] Qn 5. (a) Check whether or not the function u(x, y) = x2 2xy is harmonic. (5] (b) Use the property of harmonic functions on the components of a complex function to check whether the function f(2) = xy? + i(x2 y) is holomorphic in C. [6]