Learning a subject thoroughly is doable, if you work with a good learning system. Most challenging, for many, could be the STEM subjects. Accordingly, Self-Education Equipment and Methods is developing several sequels to the Self-Education Manual on topics in mathematics and science in the hopes that readers will learn by example how to conquer a field of study. In our sequels, we are investing time and effort on your behalf. If you then personalize the material and study, you will likely remember it.
The first sequel is the Self-Education Manual for Plane Trigonometry, to be followed shortly by another called the Self-Education Manual for Differential Equations. If you are needing help on, say algebra or geometry, or on some non-STEM field, we suggest that you first use the learning system of the Self-Education Manual and the Learning Tool Kit to learn that subject. After you have built a firm foundation of prerequisites, you may then confidently attempt to build upward on your structure of knowledge and expertise, by conquering the more advanced subjects.
Gary D. Petersen