You are looking for a multivariable calculus textbook by Edwards, Henry C., and David E. Penney, specifically the 6th edition in PDF format.
Introduction
Real-World Modeling: Integrating theoretical calculus with practical applications in physics and engineering. Resources and Study Materials Assignments | Multivariable Calculus - MIT OpenCourseWare You are looking for a multivariable calculus textbook
Conclusion
Open Educational Resources (OER): If you simply need the knowledge rather than the specific homework problems from Edwards and Penney, sites like LibreTexts or MIT OpenCourseWare offer free, legal multivariable calculus materials. Conclusion and David E. Penney
The 6th edition follows a traditional multivariable sequence with a modern conceptual emphasis: Google Books Vectors and Geometry of Space : Dot products, cross products, and lines/planes in 3D. Vector-Valued Functions : Curves in space, velocity, and acceleration. Partial Differentiation
Simply possessing the PDF is not enough. Here is a proven study strategy: You are looking for a multivariable calculus textbook
and visuals to help students visualize complex surfaces and vector fields. Matrix Approach