Limits of a function's derivative and how it relates to a function.

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SUMMARY

The discussion centers on the mathematical statement regarding the limits of a function's derivative and its implications for the function itself. Specifically, the claim is examined: if lim x->b (from the left) f'(x) = infinity, then lim x->b (from the left) f(x) = infinity. Participants express skepticism about this statement, with one contributor suggesting that it may be false and contemplating counterexamples. The hint provided about the relationship between the inverse function's derivative and the original function's derivative aids in clarifying the discussion.

PREREQUISITES
  • Understanding of limits in calculus
  • Knowledge of derivatives and their properties
  • Familiarity with inverse functions and their derivatives
  • Experience with constructing mathematical proofs
NEXT STEPS
  • Research the properties of limits and derivatives in calculus
  • Study the relationship between a function and its inverse, particularly in terms of derivatives
  • Explore counterexamples in calculus to understand the limits of derivative implications
  • Learn about the behavior of functions at points of discontinuity or critical points
USEFUL FOR

Mathematics students, educators, and anyone studying calculus, particularly those interested in the behavior of functions and their derivatives.

renjean
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Homework Statement



Prove or disprove: if lim x->b (from the left) f'(x) = infinity then lim x->b (from the left) f(x) = infinity


Homework Equations


my gut instinct is that this is false.


The Attempt at a Solution


I have thought of many counterexamples but none of them seem to work. Does it matter that the limit is at a point and not as x-> infinity?
 
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Hint: (f-1)'=1/f'(f-1(x))

What happens if f'(y)=0.
 
ah! that helps a lot. thanks for the hint!
 

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