slope tan slope m f(r) y=f(r) If()-f(a) a a O lim (x)-f(a) nx→a r-d FIGURE 3.3 Copyright@2011 Pearson Education, Inc. Publishing as Pears on Addison-Wesley Slide 3-6Copyright © 2011 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Slide 3 - 6