Proving Uniform Continuity of f+g with Triangle Inequality

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SUMMARY

The discussion centers on proving the uniform continuity of the sum of two uniformly continuous functions, f and g, using the Triangle Inequality. The user successfully demonstrated that if both functions are uniformly continuous, then their sum, f + g, is also uniformly continuous. Furthermore, they explored the case for the difference, f - g, by defining h as -g and applying the same proof strategy, confirming that f - g remains uniformly continuous. This approach leverages the property that the absolute value function is uniformly continuous.

PREREQUISITES
  • Understanding of uniform continuity in mathematical analysis
  • Familiarity with the Triangle Inequality theorem
  • Basic knowledge of real-valued functions
  • Proficiency in manipulating mathematical proofs
NEXT STEPS
  • Study the properties of uniformly continuous functions in detail
  • Learn about the Triangle Inequality and its applications in analysis
  • Explore examples of uniformly continuous functions and their sums/differences
  • Investigate the implications of uniform continuity in metric spaces
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Mathematics students, educators, and researchers interested in real analysis, particularly those focusing on continuity properties of functions.

sergey_le
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Homework Statement
I didn't understand what I was supposed to write here
Relevant Equations
I didn't understand what I was supposed to write here
I came across the following question:
If g and f are uniform continuity functions In section I, then f + g uniform continuity In section I.
I was able to prove it with the help Triangle Inequality .
But I thought what would happen if they asked the same question for f-g
I'm sorry if my English isn't good and you don't understand me
 
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Nothing should change to your proof. Check that up to minor modifications the same proof still works.

Alternatively, if you have proven that if ##f,g## is uniformly continuous, then also ##f+g## you can proceed as follows.

Show that ##h:= -g## is uniformly continuous (this will follow because ##|-x| = |x| \forall x \in \mathbb{R}## if you do the proof) and then you can apply what you already proved: ##f+h = f-g## will be uniformly continuous.
 
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thank you
 
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sergey_le said:
thank you

Welcome to physicsforums btw! Hope you have a good time here.
 
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