Factor


Press MENU 9 to access the CAS screen. Press F1 to access the TRNS (transform) menu. Press 3 to select item 3:factor. The prompt factor( is pasted into the entry line.

The syntax for factoring an algebraic expression is factor(expression). For example, let's factor x 4 - 1. After the prompt factor( in the entry line, type

X ^ 4 - 1 , X ) EXE

Hence, .

The item 3:factor initially provides a factorization over the integers. Hence, factor(x^4 - 9) is returned as (x2 - 3)(x2 + 3). To obtain a factorization over the real numbers, from the TRNS menu, press 2 to select 2:rFctor. This yields the desired complete factorization over the real numbers.

In order to obtain a complete factorization over the complex numbers, press CTRL SETUP, highlight Answer Type, press F2 to select CPIX, then press EXE. This returns you to the CAS screen.

Press F2 to select the TRNS menu, press 2 to select 2:rFctor and paste rFactor( into the entry line. Enter the expression, close the parenthesis, and press execute. For example, enter X ^ 4 - 9 , X ) EXE to factor x4 - 9. The factorization

 

is displayed.

Factor a Number

When applied to a number, factor displays the prime factorization of a given integer. To factor an integer into its prime number factors, press F1 to access the TRNS menu. Press 3 to select 3:factor. The syntax for factoring is factor(integer). For example, the screen at right displays the prime factorization for n = 1234567890.