Determining the numerical value representing the area under a curve, bounded by specified limits on the x-axis, constitutes a fundamental operation in calculus. This process involves finding the antiderivative of a given function and then calculating the difference between its values at the upper and lower limits of integration. For example, consider finding the area under the line y = 7 x between x = 1 and x = 3. This requires computing the definite integral of the function 7 x with respect to x from 1 to 3.
Calculating areas, volumes, and other accumulated quantities relies heavily on the capacity to perform this specific type of calculation. Its usefulness extends to many fields, including physics (calculating work done by a force), engineering (determining fluid flow), and economics (modeling marginal cost and revenue). The development of these integration techniques has deep historical roots, tracing back to the ancient Greeks’ attempts to find areas of irregular shapes using methods of exhaustion. Modern calculus, however, provides a systematic and efficient means for performing these computations.