About multitasking:   Recent research cited in the Washington Post Weekly, March 5-11, 2007 issue suggests that multitasking is good for getting a lot of work accomplished, but leaves the part of the brain responsible for storing and recalling information quiet. That is, long-term learning is not happening when you are multitasking, no matter how much work you are getting done. "It is almost impossible to gain a depth of knowledge of any of the tasks you do while you are multitasking. And, if it becomes normal to do, you'll likely be satisfied with a very surface-level investigation and knowledge."
    This is not to say multitaking is bad. For many things it is good and an efficient use of time. However, it is not good for learning math at a deep level. There is a big difference between "getting homework done" (multitasking works) and "learning how to do it" (multitasking fails). 
    Find a substantial block of time to study math when you are not with friends. Turn your cell phone off. Do not use your iPod (If you are listening to music, you are not doing math.) Do not check the internet. Avoid every possible distraction. Then study, with intent to learn, for an hour or two straight. Do nothing else during that block of time. Learning math takes focus.
     Do the assigned homework after learning how to do it. (Study first, then do the homework.) Some students do the homework without learning how to do the homework. Looking up how to do problems as you go along frequently fails to result in long-term learning. Looking in the solution manual frequently fails to result in long-term learning. If your study methods failed, do not continue to use the same methods. Do not persist with study habits that fail!  Make major changes!
    Many students try to memorize how to do the problems on the homework and old exams. Good. But that is not enough. There are an infinite number of different problems that can be done with Precalculus methods and you cannot memorize them all. Instead, you must learn the principles which allow you to extend the examples you have seen to examples you have not seen. That is a big difference between Algebra II and Precalculus. Precalculus students must learn how to apply familiar methods to unfamiliar examples. How do you learn principles?  Here is advice from previous students. You got a handout about how to study math.