Continuity Proof: f(x) = x^3 [cos(pi/x^2) + sin(pi/x^2)]

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SUMMARY

The discussion centers on proving the continuity of the function f(x) = x^3 [cos(pi/x^2) + sin(pi/x^2)] for x ≠ 0. Participants highlight that the function is continuous for all x ≠ 0 due to it being a composition of continuous functions. However, it is not continuous at x = 0 since the function is undefined at that point. The use of the squeeze theorem was attempted but deemed ineffective for determining the range of the trigonometric components.

PREREQUISITES
  • Understanding of continuity in mathematical functions
  • Familiarity with the squeeze theorem in calculus
  • Knowledge of trigonometric functions and their properties
  • Basic concepts of limits and their application
NEXT STEPS
  • Study the application of the squeeze theorem in detail
  • Learn about continuity and discontinuity in piecewise functions
  • Explore the properties of trigonometric functions, specifically cos(θ) and sin(θ)
  • Investigate limits involving trigonometric functions as x approaches zero
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Students studying calculus, particularly those focusing on continuity and limits, as well as educators seeking to clarify concepts related to trigonometric functions and their continuity properties.

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Homework Statement



f(x) = x^3 [cos(pi/x^2) + sin(pi/x^2)] for x≠0

Homework Equations





The Attempt at a Solution



I really am stuck.

I've tried squeeze theorem on [cos(pi/x^2) + sin(pi/x^2)], but I can't compute the range.

So, I tried doing it individually, squeezing -1 ≤ cos(pi/x^2) ≤ 1, but that doesn't work.

Any hints please?
 
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cos(θ)+sin(θ) = (√2)sin(θ + π/4)
 
What's the question exactly? You want to prove that that function is continuous?
 
The given function is obviously continuous for x\ne 0 because it is a composition of continuous functions. It obviously not continuous for x= 0 because it is not defined at x= 0.

Because I suspect the problem was not supposed to be that "obvious", please check again and tell us what the problem really is!
 

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