The formula for the exponential function and the slope of its tangent line are reported in the text boxes below the graph. Exponential function and tangent line. Drag the point to see other exponentials and their tangents. With the applet above you cannot hit the graph of e x exactly, but you can come close, and when you do you see that the tangent slope is close to 1. In fact, when the applet first starts, the exponential function is quite close to e x .
All scientific calculators provide some means of evaluating the exponential function.
For instance, on the TI-82 you would find e 2 by pressing the 2nd key followed by the LN key, then 2 and enter. The answer should be close to 7.3890560989306495. The following table explains the basic terms used in compound interest problems. The principal is the amount that you invest. The compound amount is what your investment has grown to.