612 differentiable ⇒ continuous
ᐥIf f is differentiable at c then f is continuous at c.ᐥ Define a function g by (f(x)−f(c))/(x−c) for x≠c and f(x)ᐁx「c」 at x=c. 「g(x) Ƚx→c」 = 「(f(x)−f(c))/(x−c) Ƚx→c」 ┆f is differentiable at c┆ = f(x)ᐁx「c」 So g is continuous at c. g(x) = (f(x)−f(c))/(x−c ...
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