By now, many of your students may be all excited about trigonometry. You’ve managed to persuade them that it is worth to put the efforts to comprehend the technicalities that you will explain to them. But you will also need to remind them of the importance of prerequisite knowledge. To effectively communicate the technicalities to your students, you will need to make some assumptions about their knowledge of some facts. If you choose not to do that, you may run into complications to explain basic results, such as $$1/\sqrt{3}$$ is equal to $$\sqrt{3}/3$$. That they know some algebra and geometry probably is a safe assumption. If your students use a textbook, facts abou...