F differentiable proves continuity

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SUMMARY

If a function f is differentiable at a point x, then it is also continuous at that point x. This conclusion is established using the epsilon-delta definition of continuity. The proof involves demonstrating that the limit of the difference quotient approaches the derivative f'(a) as h approaches 0, leading to the conclusion that the limit of f(x) as x approaches a equals f(a).

PREREQUISITES
  • Epsilon-delta definition of continuity
  • Basic concepts of limits in calculus
  • Understanding of differentiability
  • Knowledge of derivatives and their properties
NEXT STEPS
  • Study the epsilon-delta definition of continuity in detail
  • Learn about the relationship between differentiability and continuity
  • Explore advanced proofs involving limits and derivatives
  • Investigate examples of functions that are differentiable but not continuous
USEFUL FOR

Students studying calculus, mathematics educators, and anyone interested in the foundational concepts of analysis and the relationship between differentiability and continuity.

mike1967
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Homework Statement



If f is differentiable at x then f is continues at x

Any help would be great.


Homework Equations



MUST USE epsilon delta definition to prove

The Attempt at a Solution

 
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I can prove like this:

(sorry I don't know how to make look fancy)



lim f(a+h) - f(a)/h = f'(a)
h->0

lim [f(a+h) - f(a)/h]*h = f'(a)*(h=0)
h->0

lim f(a+h) - f(a) = 0
h->0

lim [f(a+h) - f(a)]+f(a) = 0+f(a)
h->0

x= a+h h=x-ah

lim f(x) = f(a)
x->a
 

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