Finding a derivative from the limit definition

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SUMMARY

The discussion focuses on finding the derivative of the function f(x) = x1/3 using the limit definition of a derivative. Participants emphasize the importance of simplifying the numerator to eliminate the variable h in the denominator. The key formula discussed is (a1/3 - b1/3)(a2/3 + a1/3b1/3 + b2/3) = a - b, which is crucial for manipulating cube roots in the limit definition.

PREREQUISITES
  • Understanding of limit definitions in calculus
  • Familiarity with derivatives and their properties
  • Knowledge of algebraic manipulation involving cube roots
  • Experience with the formula for the difference of cubes
NEXT STEPS
  • Practice using the limit definition of derivatives with other functions
  • Explore the application of the difference of cubes formula in calculus
  • Learn about higher-order derivatives and their calculations
  • Investigate the implications of derivatives in real-world scenarios
USEFUL FOR

Students studying calculus, particularly those learning about derivatives and limit definitions, as well as educators seeking to enhance their teaching methods in these topics.

Jimmy25
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Homework Statement



Find the derivative of f(x)=x1/3 using the limit definition of a derivative.

Homework Equations





The Attempt at a Solution



I am stuck once I plug the numbers into the limit definition equation. How can I simplify the numerator in such a way the the h in the denominator will cancel when both the numbers in the number are cube roots?
 
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Show us what you have and where you're stuck.

You're going to want to use this idea : (a - b)(a2 + ab + b2) = a3 - b3. This formula can be modified to work with cube roots, like so. (a1/3 - b1/3)(a2/3 + a1/3b1/3 + b2/3) = a - b.
 
Edit: Don't worry, Mark got it better than me
 

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