How can I prove the limit of a quotient using the definition of derivative?

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SUMMARY

The discussion focuses on proving the limit of a quotient using the definition of the derivative, specifically for functions f and g where f(z(0)) = g(z(0)) = 0 and g'(z(0)) ≠ 0. The limit is established as lim z->z(0) (f(z)/g(z)) = f'(z(0))/g'(z(0)). The key equations referenced include the definition of the derivative: f'(z(0)) = lim z->z(0) (f(z) - f(z(0)))/(z - z(0)). Participants emphasize the importance of carrying the limit operator through the simplification process.

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Homework Statement



Supposed f(z(0))=g(z(0))=0 and that f'(z(0)) and g'(z(0)) exist where g'(z(0)) is not equal to 0. Use definition (10, section 19 of derivative to show that :

lim z->z(0) (f(z)/g(z))=f'(z(0))/g'(z(0))


Homework Equations



definition 1: f'(z(0))=lim z->z(0) f(z)-f(z(0))/(z-z(0)

The Attempt at a Solution



f'(z(0))= lim (z->z(0)) f(z)-f(z(0))/(z-z(0))=f(z)-0/(z-z(0))=f(z)/(z-z(0)); Not sure where I should with with this proof. Help.
 
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You started off really good, except you forgot the carry the limit operator through, which is important. Now that you've simplified f'(z(0)), do the same for g'(z(0)) ! Remember to use all the information you're given.
 

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