Calculus:Math 21C, Fall 2010Summary of topics covered after Midterm 21. Functions of several variablesPlots.Graphz=f(x, y) of a functionf(x, y) of two variables.Contourplots of level curvesf(x, y) =c. Level surfacesf(x, y, z) =cof a function ofthree variables.Sets, limits and continuity.Open and closed sets inR2andR3. Interiorpoints and boundary points.Limits and continuity of functions of severalvariables.(Intuitive ideas and examples only.Noϵ-δdefinitions or proofswill be required for the final.)Derivatives.Interpretation of the derivative as the local linear approxima-tion of a function.