Find a formula for a constant function using the mean value theorem

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SUMMARY

The discussion centers on proving that if the derivative of a function f'(x) = 3x^2, then the function can be expressed as f(x) = x^3 + c for some constant c in R, utilizing the Mean Value Theorem. Participants noted the importance of recognizing that two functions with the same derivative do not necessarily equate unless additional conditions are met. The conclusion emphasizes that the constant function can be derived from manipulating the relationship between f(x) and its derivative.

PREREQUISITES
  • Understanding of the Mean Value Theorem
  • Knowledge of derivatives and their properties
  • Familiarity with polynomial functions
  • Basic algebraic manipulation skills
NEXT STEPS
  • Study the Mean Value Theorem in detail
  • Explore the properties of polynomial functions and their derivatives
  • Learn about the implications of constant functions in calculus
  • Practice problems involving derivatives and function proofs
USEFUL FOR

Students studying calculus, particularly those focusing on derivatives and the Mean Value Theorem, as well as educators looking for examples of function proofs.

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Homework Statement


Let x ϵ R such that f'(x) = 3x^2. Prove that f(x) = x^3 + c for some c ϵ R using the Mean Value Theorem.


Homework Equations





The Attempt at a Solution


I used two functions f(x) and g(x) that have the same derivative namely f'(x). Applying the theorem I am able to work up until f(x) = g(x), I am unsure of where to go from there.
 
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If you reached the conclusion [tex]f(x) = g(x)[/tex] from only the hypothesis [tex]f'(x) = g'(x)[/tex], something is clearly wrong, since that deduction is false.

You have a function that's expected to be a constant, namely [tex]f(x) - x^3[/tex]. Work with that.
 

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