Hy guys! I would like to ask your help with one of my math problem I cannot solve. I have two function, Q(x,y) and P(x,y). I would like to know f(x,y) if df(x,y)=P(x,y)dx+Q(x,y)dy. I understand the right side of the equality but I don't know the left one's meaning. If the right one is calculated what my next step is? Thanks