Can the product rule be applied if one of the functions is not differentiable? For example,(adsbygoogle = window.adsbygoogle || []).push({});

f(x)={g(x)sin(1/x), x not =0

=0, x=0

where g(0)=g'(0)=0.

f'(0)=g'(0)sin(1/0) + g(0)dsin(1/x)/dx

=0sin1/0+0dsin(1/x)/dx=0?

applying the limit definition, I get

f'(0)=g'(0)lim sin(1/h) where h-->0

is this zero?

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# Homework Help: Product rule

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