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Problems Based on Continuity of Functions

A function is said to be continuous in the interval [a, b] [a, b] if it is continuous at all points in the interval.

The characteristics of continuity of functions manifest themselves in various aspects of nature. The flow of time in human life is continuous. Similarly, in mathematics, there is the concept of function continuity. 

The simple meaning is that if you can sketch a curve on a graph without lifting the pen, the function is continuous (assuming you are good at drawing). This is very simple and close to an accurate definition. But for more advanced mathematics, we need to define it more accurately. 

For a function to be continuous at a point, the value of the function at that point must be equal to the value of the limit at that point. Also, it must be defined at that point, and its limit must exist at that point. A function is considered to be continuous over an open interval if it is continuous at all points in the interval. 

Another continuity of functions has points where breaks occur (in the graph), but they satisfy this property at intervals within their domain. Limits and continuity to develop a viable theory should limit the class of functions you are considering. 

You can infer from such limits. Studying continuous functions is a classic example of having a function. Continuously, we get enough information to derive a strong theorem, such as the intermediate value theorem. In fact, many functions that occur in real-life problems are stable. This is the definition of continuity of functions. It is aesthetically and practically attractive. 

How to prove continuity of functions? 

The definition of continuity provides a lot of information about a function. Fortunately for us, many natural features are continuous and not. 

There are three main techniques: You can do one of three things to indicate that the function is continuous: 

  1. Show that the following definition of continuity is met. 
  2. This indicates that the definition of continuity -δ is satisfied.
  3. Break it down into simpler functions that we already know.

The most direct approach is:

To indicate that the function is continuous, it means that it meets the definition of continuity. In other words, if there is a convergence sequence. For domains, the image of the sequence converges (towards the right limit). 

Please note this should be true for all convergence sequences and cannot be shown to work in only one sequence. This is often a good clean approach to simple functions because you can use restriction rules. For all points in interval I, the function f (x) is called continuous in interval I = [x1, x2] if the above three conditions are met. 

However, note that at the endpoints of interval I, it is unnecessary to consider both the right and left limits in calculating Lim x → an f (x). If a = x1, only the right limit needs to be considered, and if a = x2, only the left limit needs to be considered.

Definition of continuity

If the limit when approaching x = a is equal to the value at x = a, then the function is continuous at x = a. The definition of continuity in calculus is largely based on the concept of marginal. If the limit is a bit vague, the function limit is the value of f (x), where the function approaches a particular value of x.

Limits and continuity

The idea of margins is one of the vital matters to apprehend on the way to put together a calculus. The restriction is the variety of instance features tactics, while the impartial variable of the feature tactics has a specific value. 

For example, if the feature f (x) = 3x, we will say “the restrict of f (x) while x tactics 2 is 6”. Symbolically that is written as f (x) = 6. The subsequent segment offers examples of feature limits that will help you outline extra elements and clarify the idea.

Define continuity of a function

If you can draw a curve on the graph without lifting the pen, the function is called continuous. According to the definition of continuity, the function f (x) is continuous at the point x = a, and in that region, when f (a) is satisfied, the limit of the function exists at x = a and f (x) x = a and F(a).

Conclusion

In order for a function to be continuous at a certain point, it should be defined for that point as its limit exists at that point. The value of the function should be equal to the value of the point’s limit. Here, discontinuities can be categorised as unstable, removable, or infinite. 

If it is continuous at all points and endpoints inside, it is continuous at closed intervals. The theorem for compound functions states: 

If f (x) is continuous with L and 

 lim → ag (x) = L, then 

 lim x → af (g (x)) = f (lim x → ag (x)) = f (L).