This is a common question about why definite integration and infinite series are not covered in Worldwide Differential Calculus.  The answer is quite simple, the second volume in the Worldwide Calculus series – “Worldwide Integral Calculus, with Infinite Series” will cover both topics, although there is “warm-up” material covered in Worldwide Differential Calculus as professor Massey notes in the preface.

More from the preface-

“When discussing polynomial functions, in Section 2.1, we introduce the sigma notation for summations. Our approach to the exponential function in Section 2.4 requires us to briefly discuss sequences of numbers and functions, geometric series, and power series. In addition, while we use a traditional approach to defining, and working with, sine and cosine, we discuss their power series at the end of Section 2.7. It is our hope that these introductions to summations, sequences, and series will make those topics more comprehensible when they are dealt with in depth in Worldwide Integral Calculus, with Infinite Series.”

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