*  Reading Outline, Sec2.6 *
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* Vocabulary/Definitions *
 - Differentiability
 - Conditions under which a function will not be differentiable
 - Does continuity imply differentiability?
 - Does differentiability imply continuity?


* Understand *
1. Where is the function f(x) = |x^2 - 4| not differentiable?


2. Show by using the definition of the derivative that f(x) is not
differentiable at one of the points you identified in (1).