<p>To learn the alternate definition of a derivative at a point, students will plug the f<img src="/xwiki/resources/icons/silk/cancel.gif" class="wikimodel-freestanding" alt="cancel"/>=sqrt<img src="/xwiki/resources/icons/silk/cancel.gif" class="wikimodel-freestanding" alt="cancel"/> into the definition. With algebra techniques like either the difference of squares or rationalizing the numerator, they will discover the derivative. This worksheet should be given to groups of 3 or 4 to discuss their way through it and understand it both graphically & analytically. Hat tip to the works of Paul Foerster!</p>