The inverse process of derivatives called anti–derivatives or integration.
“A function being given and it is required to find a Second function whose derivative with respect to x, is, that is,
Thus if
Then
The function , then, is called the antiderivate or indefinite integral of .
Symbol of Integration:
The function is called integrand and the symbol is called the integral sign.
Thus, means that is to be integrated with respect to (w.r.t) ‘x’ and is read as “Integral of ”. Where dx indicates the variable with respect to which is to be integrated.
Note:

In , where ‘c’ is called as the constant of integration.

and are inverse operations of each other.