As Feliciano and Uy themselves might say, at the end of the chapter’s answer key (printed in the back, always with just the final answers, no full solutions): “Now proceed to Chapter 11: The Definite Integral.” Because calculus, like learning, never truly ends — it only accumulates. Page numbers, exact problem statements, and subsection titles vary by edition (e.g., the 1978 SIBS Publishing edition vs. the 1990s reprints). However, the structure and spirit of Chapter 10 have remained remarkably consistent — a testament to the timeless pedagogy of Feliciano and Uy.
Yet the chapter does not coddle. The difficulty ramps up sharply. By the last set of problems, students face (e.g., $x^3 + y^3 = 6xy$, the folium of Descartes) and must find tangents, normals, and extreme values without explicitly solving for $y$. This prepares them for higher-level courses like differential equations and multivariable calculus. A Cultural Touchstone In the Philippines, Feliciano and Uy is more than a textbook — it’s a cultural artifact. Chapter 10, in particular, is where study groups form, where tutors earn their keep, and where many students first encounter the satisfying click of a difficult word problem solved correctly. The shared trauma of “the ladder problem” or “the box problem” creates camaraderie. As Feliciano and Uy themselves might say, at
The section is particularly feared. One problem might involve a lighthouse rotating its beam, a moving ship, and the speed of the light spot along a shore — requiring implicit differentiation with respect to time, the chain rule, and trigonometric substitution all at once. Pedagogical Philosophy: Why It Works Chapter 10 exemplifies a teaching philosophy that prioritizes application over abstraction . Feliciano and Uy were writing for students who would become practitioners — civil engineers calculating beam deflections, electrical engineers analyzing rates of change in circuits, business students finding break-even points. The chapter does not spend pages proving the Mean Value Theorem (that appears earlier, in Chapter 4). Instead, it shows how to use derivatives to solve a concrete problem. However, the structure and spirit of Chapter 10
Moreover, the chapter introduces — problem-solving strategies. For optimization, students are taught: 1) Draw a diagram. 2) Identify the quantity to be optimized. 3) Express it in terms of one variable. 4) Differentiate. 5) Test critical points. This recipe-like clarity is comforting to students who find pure mathematics intimidating. By the last set of problems, students face (e
The answer lies in what technology cannot do — at least not yet. A computer can differentiate $12x - 4x^2$, but it cannot look at a real-world scenario, identify the relevant variables, and translate the situation into a mathematical model. Chapter 10 trains exactly that skill: reading a word problem, drawing a diagram, defining variables, and setting up the equation. This is the essence of mathematical modeling , a skill invaluable in data science, engineering design, and operations research.