Continuity With Piece Wise Functions

In summary: In order to make this function continuous for all real numbers, we need to have ##\frac{\sin(x)}{\cos(x)} = 1## when ##x \ge 0## and ##\frac{\sin(x)}{\cos(x)} = a## when ##x < 0##. Therefore, for this function to be continuous, ##a## must equal 1. In summary, the constant a must equal 1 for the function f(x) = ax/tan(x) to be continuous for all real numbers.
  • #1
Michele Nunes
42
2

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.
 
Physics news on Phys.org
  • #2
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)}}##
 
  • Like
Likes Michele Nunes

Related to Continuity With Piece Wise Functions

1. What is a piecewise function?

A piecewise function is a mathematical function that is defined by different rules or equations for different intervals of the input variable. This means that the function may have different forms or behaviors in different parts of its domain.

2. How do you determine continuity of a piecewise function?

To determine continuity of a piecewise function, you need to check if the function is continuous at each point where the different pieces meet. This means that the limit of the function from the left side of the point must be equal to the limit from the right side of the point, and the value of the function at that point must also be equal to these limits.

3. Can a piecewise function be continuous everywhere?

Yes, a piecewise function can be continuous everywhere if all of its pieces are continuous and the limits match at each point where they meet.

4. How is continuity of a piecewise function important in real-world applications?

In real-world applications, continuity of a piecewise function is important because it allows us to model and predict behaviors of systems or processes that may have different rules or behaviors at different points. This can be seen in areas such as physics, engineering, and economics.

5. What are the common types of piecewise functions?

The common types of piecewise functions are step functions, absolute value functions, and periodic functions. Step functions have a constant value on different intervals of the input variable, absolute value functions have a "V" shape with different slopes on each side of the vertex, and periodic functions repeat the same pattern over and over again with different equations for each interval.

Similar threads

  • Calculus and Beyond Homework Help
Replies
27
Views
795
  • Calculus and Beyond Homework Help
Replies
26
Views
938
  • Calculus and Beyond Homework Help
Replies
1
Views
364
  • Calculus and Beyond Homework Help
Replies
8
Views
912
Replies
14
Views
1K
  • Calculus and Beyond Homework Help
Replies
3
Views
850
  • Calculus and Beyond Homework Help
Replies
2
Views
330
  • Calculus and Beyond Homework Help
Replies
5
Views
930
  • Calculus and Beyond Homework Help
Replies
17
Views
2K
  • Calculus and Beyond Homework Help
Replies
2
Views
1K
Back
Top