Multivariable calculus, class #7: Differentiability of multivariable functions

Mathematician spotlight: Piper Harron We review differentiability for single-variable calculus. Then we discuss the definition and meaning of differentiability for multivariable functions. We compute one limit of a differentiable function (which comes out to 0) and one limit for a point of non-differentiability (which comes out nonzero).