Hello everyone, I have a few questions about derivatives and tangents. Last year I was awesome at derivatives but for some reason it is taking me a bit to bet back into them. 1) If the the tangent line to y=f(x) at (4,3) passes through the point (0,2), find f(4) and f '(4). For this question I wasn't really sure what to do. But I found the slope of the tangent using the slope forumula and the points (4,3) and (0,2). I found this slope to be (1/4). Then I found the equation of the tangent line to be y=(1/4)x+2. I'm not really sure where to go with this now. If the equation I just figured out is the equation of the tangent line it is the equation of the derivative of the function so to find f '(4) I should just be able to stick 4 into that right? But how would I find f(4)? I must be doing something wrong because I know I shouldn't have to get into intergrals yet.....that doesnt come for awhile. I think I must be misunderstanding the question or something. 2) The limit represents the derivative of some function f at some number a. State such an f and a this case. (lim as x approaches pi/4) (tanx-1)/(x-pi/4). I have absolutely no idea how to go about this one, limits and derivatives of trig functions has always been a weak spot for me. There is one more question that I have but I am going to try and keep working on it before I ask it here, I think I might be close to understanding it. Thanks a lot guys.