Introduction to Three Dimensional Geometry and Projection Op

This textbook is written to develop thorough understanding the mastery behind the foundations of geometry that needed to solve geometric problems using vectors in three dimensional Euclidean space at a useful proficiency level, it introduces a comprehensive study on three dimensional Euclidean spaces' objects, namely; points, line segments, vectors, straight lines, planes, spheres, cylinders, quadratic surfaces in general analytically, and includes different comparisons between such studied objects among themselves, it focuses on the orthogonal projections of a point and directed line segment on line, on plane, and on sphere, and it is recommended world widely for the second level universities' students, its contents are written in a systematic, streaming, understandable and attractive way for student's interest, supported with adequate number of examples, exercises, problem solving and applications to meet the quality standard. Moreover; it is a prerequisite for some other fields of study, like Descriptive Geometry, Differential Geometry, Analytical Geometry, Algebraic geometry, Injective Geometry and some others.