AP credit, a necessity?

<p>Hm.. I've got to take a year of math for premed, so I'll probably go the 3A, 3B, 3C route. So my question to you guys would be whether it would be wise to opt out of 3A with my AB calc score from sophmore year. I only got a 3 on the test though (i think i was deceived by the ease of the class, so i figured i was a natural, never studied and it bit me in the ass). Jr. year I took IB math 2, and got a 6 on that test, and now i haven't taken any math for a year, so i'm rusty at best...
So would it be unwise to forego the AP credit and take all three quarters? I mean, how useful (credit wise) could it be to just skip 3A anyway? If i do decide to skip it, would I have to prep extensively for 3B because it'd be a continuation of 3A, or are they totally different classes?</p>