Hi all,(adsbygoogle = window.adsbygoogle || []).push({});

our professor wrote this proof (using the definition of derivative), that the derivative of constant function is 0:

[tex]

f(x) \equiv a

[/tex]

[tex]

f^{'}(b) = \lim_{h \rightarrow 0} \frac{f(b+h) - f(h)}{h} = \lim_{h \rightarrow 0} \frac{a - a}{h} = 0

[/tex]

I'm not sure about the last step, because we have0denominator, don't we? Why isn't it here considered an indeterminate expression?

Thank you.

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# Derivative of constant function - proof

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