Education Technology

# Knowledge Base

## Solution 11826: Calculating nth Power and Roots Using the TI-89 Family, TI-92 Family, and Voyage™ 200 Graphing Calculators.

### How do I perform nth power and root computations using the TI-89 family, TI-92 family, and Voyage™ 200 graphing calculators?

The instructions will detail how to perform the nth power and root computations on the TI-89 family, TI-92 family, and Voyage 200.

Powers
To raise a number by an exponent, use the carat (^) key, located above the division key. For example, to raise 3 to the 4th power, press [3][^][4][ENTER] for the result of 81. And, to find -22, enter (-2)^2.

Roots
Taking the nth root of a number is the same as raising the number to the 1/x power. Refer to the examples provided below.

Example:  Find the cube root of 27

1) Enter 27 and press [^].
2) Press [(] and enter 1.
3) Press [÷], enter 3 and press [ )] [ENTER].

The screen will display 3.

Example: Find the cube root of -27

1) Press [( ] [(-)] and enter 27.
2) Press [ )] [^] [( ] and enter 1.
3) Press  [÷], enter 3, and press [ )] [ENTER].

The screen will display -3.

OS 3.10 has a built in root function. The steps provided below can also be used for the TI-89 Titanium or Voyage 200 with OS 3.10 or higher to calculate the cube root of 27.

1) From the HOME screen, press [GREEN DIAMOND] [9] and the root( function will populate in the entry line.
2) Input 27, press [,] and enter 3.
3) Press [)] [ENTER].

The screen will display 3.

Please Note: It is necessary to put parentheses around the negative number because these calculators evaluate negation with the same priority as multiplying by a negative 1. This must be done before the number is raised to the exponent

Please see the TI-89 family and Voyage 200 guidebooks for additional information.