I bought this book for my trig class. It was quite useful. It has step by step answers. It doesn't have all of the answers, only the odds. There are also problems, in which it says "Writing and Discussion" or "See Answer In Text". It was frustrating having to use my text book after I put it away.
I had bought this for my Pre-calculus class in college. It was definitely worth the buy. They show step by step how they got the answer to all the odd problems. For someone who is a visual learner, this gave me and edge over the other students. Although it helped me, it depends on the person. Some people may still not understand and therefore don't recommend it if that is the case. Otherwise, this product was worth every single penny.