e-book
Trigonometry and single phase AC generation for electricians
"To understand electrical theory, it is important to have a grasp of trigonometry. Whether we are talking about single phase or polyphase power, trigonometry is a key concept. This textbook, divided into three sections and provides easy-to-understand and enjoyable lessons on trigonometry, vectors, and AC generation for those training and working as electricians"--BC Campus website.