The concept of limit in calculus serves as a foundational building block that enables us to comprehend the behavior of functions as they approach specific values. At its core, a limit signifies the value that a function is “approaching” as its input, or independent variable, gets closer and closer to a particular point.
Limit is the fundamental concept that describes the relationships between central to unlocking the function variable and the calculus power for analyzing various phenomena across mathematics, science, and engineering. In this article, we will cover the concept of limit along with its definition, properties, and application.
Limit in Calculus
In calculus, a limit represents the value a function approaches as its input approaches a certain point, indicating the behavior of the function at that point without necessarily reaching it. Symbolically, the limit of a function (f(x)) as (x) approaches (a) is denoted as lim x → a f(x).
lim x→a f(x) = N
Algebraic Properties of Limits:
If lim x → c f(x) and lim x → c g(x) exist and c is a constant, then
I. Constant limit => constant
lim x → c k =k, where k is the constant.
II. Limit of Sum/Difference = Sum/Difference of Limits
lim x → c [f(x) ± g(x)] = lim x → c f(x) ± lim x → c g(x)
III. Limit of Product = Product of Limit
lim x → c [f(x). g(x)] = lim x → c f(x). lim x → c g(x)
IV. Limit of Quotient
lim x → c [f(x)/ g(x)] = lim x → c f(x)/ lim x → c g(x)]
Types of Limit Calculus
In calculus, limits are fundamental concepts that help us understand the behavior of functions as they approach particular values. There are several types of limits, each serving a separate purpose in mathematical analysis. Here are some common types of limits in calculus, along with explanations for each:
Limit at a Point (One-Sided Limit):
Definition: The limit of a function f(x) as “x” approaches a specific point “c” from either the left (denoted as c−) or the right (denoted as c+) is a one-sided limit.
Notation: limx→c−f(x) and limx→c+f(x).
Explanation: This limit helps us elaborate the behavior of a function as it approaches a particular point from one direction (either moves from the left or right).
Definition: The limit of a function f(x) as “x” approaches a specific point “c” in which resolves the limiting value from both sides such as left and the right is called a two-sided limit.
Explanation: This is the most common type of limit that we use to determine the behavior of a function as it approaches to a specific point “c”.
Limit at Infinity:
Definition: The limit of a function f(x) as x approaches infinity or negative infinity is called a limit at infinity.
Notation: limx→∞f(x) or limx→−∞f(x).
Explanation: This type of limit helps us understand the long-term behavior of a function as it approaches infinity or negative infinity.
Limit as x Approaches a Finite Value:
Definition: The limiting value of a function f(x) is “L” as “x” approaches to a finite value is called a limit as “x” approaches to a finite value.
Explanation: This limiting value is used to tell the function is convergent as it approaches a finite value “L”.
Limit of a Piecewise Function:
Definition: The limiting value of the piecewise functions (functions defined differently for different intervals), is determined by calculating the limits for each piece of function separately.
Notation: limx→cf(x), where f(x) is defined differently for x<c and x>c.
Infinite Limit (Divergent Limit):
Definition: The limiting value of this type of function approaches an infinite number such as a positive or negative infinity these types of functions are called infinite or divergent limits.
Notation: limx→cf(x) = ∞ or limx→cf(x) = −∞.
Explanation: Infinite limits occur when a function’s value is undefined on the given point (from right or left side).
How to Find the Limiting Value of a Function?
You can find the limiting value of a function by applying the rules of limit calculus to the given function and then substituting it in the specific point. Here, we will discuss the concept of limit in calculus with the help of examples.
Determine the limit
lim x → 5 (3x3+ 8x +3)
With the help of property, we separate the limit into three separate limits.
lim x → 5 (3x3+ 8x +3) = lim x → 5 (3x3) + lim x → 5 (8x) + lim x → 5 (3)
Step 2: Put limit value
lim x → 5 (3x3+ 8x +3) = 3(5)3 + 8(5) + (3)
Step 3: Simplification the question
lim x → 5 (3x3+ 8x +3) = 3(125) + 40 + 3
- 315 + 43
limx→-3 [(2x2 -x + 1)/(x-1)]
Evaluate the function limit.
By using the quotient property of limit we find the limit of the given function.
Step 1: Separate the limit of the function
limx→-3 [(2x2 – x + 1)/(x-1)] = lim x→-3 [(2x2 – x + 1)/ lim x→-3 (x-1)
Step 2: Separate the limit and put a limit to all given function nominators and denominators.
=> [lim x→-3 (2x2) – lim x→-3 (x) + lim x→-3 (1)] / [lim x→-3 (x) – lim x→-3 (1)]
Step 3: for simplification put the value of x.
limx→-3 [(2x2 -x + 1)/(x-1)] = [2(-3)2 – (-3) +1]/ ((-3) – 1)
limx→-3 [(2x2 -x + 1)/(x-1)] = (18 + 3 + 1)/ (-4)
limx→-3 [(2x2 -x + 1)/(x-1)] = (18 + 4)/ (-4)
limx→-3 [(2x2 -x + 1)/(x-1)] = -22 / 4
limx→-3 [(2x2 -x + 1)/(x-1)] = -5.5
A limits calculator could be a handy tool to cross-check the results for better accuracy.
Q # Number 1:
How is the limit calculated?
To calculate a limit, you evaluate the function as x gets closer and closer to the specified point. If the function approaches a single value or becomes arbitrarily close to it, that value is the limit. Techniques like factoring, rationalizing, and L’Hopital’s rule may be used to simplify calculations.
Q # Number 2:
What is the limit at infinity?
The limit as x approaches positive or negative infinity refers to as a limit at infinity. If the function’s values approach a specific value L as x becomes very large (positive or negative), then that value is the limit at infinity.
Q # Number 3:
What does a function’s continuity mean?
If a function’s limit at a given place equals the value of the function there. This function is continuous at that location. In other words, the function’s graph does not abruptly leap or break at that point.
In this article, we have discussed the details of limit in calculus with the help of the concept of limit, definition, and application of limit in calculus. For a clearer understanding, we have explained the topics by using solved examples.