Calculus is a branch of mathematics that focuses on change and motion. Two fundamental operations in calculus are differentiation and integration, which help to describe how things change and accumulate. These two concepts are not just essential in mathematics but also have practical applications in physics, economics, engineering, and even biology.
At the core of calculus, differentiation and integration are inverse operations, each with its specific purpose:
Differentiation: It is the process of finding the rate of change or the slope of a function at any point. In simple terms, differentiation tells you how a quantity changes as the input changes. The result of differentiation is called a derivative.
Integration: It is the reverse of differentiation. Integration is the process of finding the total accumulation of a quantity or the area under a curve. The result of integration is called an integral.
Together, these operations allow mathematicians and scientists to model and understand change and accumulation in the real world.
1. Differentiation Example: Differentiate
Solution:
f'(x) = 2x
Explanation: The derivative of x^2 is 2x, which tells you how the value of the function changes as x changes.
2. Integration Example: Integrate f(x) = 2x
Solution:
Explanation: The integral of 2x with respect to x gives where C is the constant of integration.
Both differentiation and integration are applicable to trigonometric functions, and the rules differ slightly for each.
In calculus, differentiation and integration play complementary roles. Differentiation breaks down a function into its rate of change, while integration provides the means to accumulate those changes. This connection between the two operations is formally described by the Fundamental Theorem of Calculus, which states:
This theorem demonstrates that differentiation and integration are inverses of each other, providing a powerful way to solve real-world problems involving motion, growth, and area.
There are a few essential rules and formulas that govern both differentiation and integration. Let’s look at some of the most important ones:
(Session 2025 - 26)