This e-book Questions & Answers Functions of Two and Three Variables Book 1 aimed to help students in topic Differentiation. Targeted users for this e-book is for students who take course Calculus in university. Mathematical tips and formulas will be placed in accordance to the subtopics whilst each differentiation questions will be displayed based on the syllabus. At the end of the topic, targeted students should meet up with the lecturer on the subject of Calculus to discuss over the answer of mathematics question. With the existence of this e-book, hopefully it will be beneficial and give positive impact on teaching and learning for students and lecturers as a whole.