Continuity With Piece Wise Functions

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SUMMARY

The discussion focuses on determining the values of the constant a that ensure the piecewise function f(x) = ax/tan(x) for x ≥ 0 and f(x) = a² - 2 for x < 0 is continuous for all real numbers. Participants noted that the first part of the function is undefined at x = 0, complicating continuity. The limit lim (x → 0) (sin x)/x = 1 is crucial for evaluating the behavior of f(x) as x approaches zero, leading to the conclusion that a must equal 2 for continuity.

PREREQUISITES
  • Understanding of piecewise functions
  • Knowledge of limits and continuity in calculus
  • Familiarity with trigonometric identities
  • Experience with evaluating limits involving tan(x) and sin(x)
NEXT STEPS
  • Study the properties of piecewise functions in calculus
  • Learn about limits involving trigonometric functions
  • Explore the concept of continuity and its implications in real analysis
  • Practice solving problems involving limits and continuity with various functions
USEFUL FOR

Students studying calculus, particularly those focusing on limits and continuity, as well as educators looking for examples of piecewise function analysis.

Michele Nunes
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Homework Statement


Determine all values of the constant a such that the following function is continuous for all real numbers.
f(x) = ax/tan(x), x ≥ 0
= a2 - 2, x < 0

Homework Equations

The Attempt at a Solution


I tried so many different ways to get the first part of the function to be defined at 0 but nothing worked, I tried manipulating it with a bunch of trig identities and no matter what, that first part is always undefined at 0 so I don't know how the function can ever be continuous if that first part of the function is always going to be undefined at 0 and I can't remove it.
 
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Michele Nunes said:

Homework Statement


Determine all values of the constant a such that the following function is continuous for all real numbers.
f(x) = ax/tan(x), x ≥ 0
= a2 - 2, x < 0

Homework Equations

The Attempt at a Solution


I tried so many different ways to get the first part of the function to be defined at 0 but nothing worked, I tried manipulating it with a bunch of trig identities and no matter what, that first part is always undefined at 0 so I don't know how the function can ever be continuous if that first part of the function is always going to be undefined at 0 and I can't remove it.
This limit will be helpful:
$$\lim_{x \to 0} \frac {\sin x} x = 1$$

Note that ##\frac{ax}{\tan(x)} = a \frac x {\frac{\sin(x)}{\cos(x)}}##
 
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