∂u/∂x =e^x cos(y) , ∂2u/∂x2=e^x cos(y)
∂u/∂y= -e^x sin(y) , ∂2u/∂y2= -e^x cos(y)
∂2u∂x2+∂2u∂y2=e^x cos(y)+ (-e^x cos(y))
∂2u∂x2+∂2u∂y2=0.
∴ U is the harmonic function
Ux=Vy
∴Vy=e^x cos(y) .
f(z)=u+iv= e^x cos(y)+i(e^x cos(y))=e^z+c
f(z)=e(x+iy)=e^x∗eiy=e^x(cosy+icos(y))=e^xcosy+i e^xcos(y).