Calculus 1 Lecture Notes, Section 3.1

If you look at a small enough region of a function near a given point, the function can be approximated pretty well by its tangent line at that point. Here is a graph of the function y = f(x) = x3 –3x2 + 2x + 1 and its tangent line at the point (2,1). The equation of the tangent line is y = 2x – 3. ................
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