Minimum Option


The minimum option is used to find a relative minimum. Press .



Press . (The minimum option can also be obtained by using the  to select option 3 and pressing .) Since a function may have more than one relative minimum, specify an interval containing the desired low point on the graph. (The function in the upper left-hand corner indicates finding a relative minimum on the graph of the given function.)



The question "Left Bound?" appears at the bottom of the screen. Use the  to move the blinking cursor to the left of the relative minimum. Press .



The question "Right Bound?" appears at the bottom of the screen. Use the  to move the blinking cursor to the right of the relative minimum. Press .



The arrows at the top of the screen indicate the boundaries between which the calculator will give the relative minimum. (The arrows must point toward each other.) The question "Guess?" appears at the bottom of the screen. Locate the cursor between the established boundaries. Press .



The coordinates of the minimum appear at the bottom of the screen. In this case, the minimum point is (2,-7/6).


Note:

The minimum option finds the minimum in the specified interval within 0.00001. Results may be slightly different than algebraic solutions. The minimum option finds a local minimum within a defined interval. Consider finding a minimum over a new interval.
 

Within this interval, the function never reaches a turning point. However, there is a minimum within that interval, and the TI-83 finds it.

 

For a specific example of finding a minimum, read Exercise 5 of the Skill Building Exercises in the Prologue of Precalculus: Making Connections.