I am given the following problem.
Let $Ω\subset \mathbb{C} $ and let $h \in C^1(Ω)$ be such that $\frac {\partial h} {\partial z}=0$. Show that $h(z)=\overline {f(z)}$ for some $f$ analytic in $Ω$.
The $\frac {\partial h} {\partial z}$ notation is mysterious to me. But, after looking at this, I have a guess as to what it means.
Write $h(x+iy)=u(x,y)+iv(x,y).$ Then $\frac {\partial h} {\partial z}=\frac {[u_x+iv_x]-i[u_y+iv_y]} 2=\frac {u_x+v_y+iv_x-iu_y} 2$. Is this interpretation correct?