ABSTRACT

Integrals play a twofold role in calculus. The so-called indefinite integral is an operation inverse to differentiation: the integral of function f (x) is a function whose derivative gives us f (x). We have seen the importance of derivatives throughout the textbook, and naturally the inverse operation also plays an important role in mathematical and economic analysis. Later, in Chapter 12, we study relations between quantities and their rates of change − the so-called differential equations. Solving differential equations is impossible without indefinite integrals.