Texas Instruments TI-89 Titanium User Manual

Activities 727
Exploring cos(x) = sin(x)
This activity uses two methods to find where cos(x) = sin(x) for the values of x between 0
and 3p.
3. Use
rref( ) to “row reduce” matrix b:
The result will have the identity matrix in
the first three columns and
a^L1 in the last
three columns.
Note: Use the cursor in the history area to
scroll the result.
4. Solve for the value of
x that will cause the
inverse of the matrix to be invalid.
Enter:
solve(getDenom( 2 ± [1,4] )=0,x)
Result:
x= L70/17
Note:
Use the cursor in the history area to
scroll the result.

Texas Instruments TI-89 Titanium Specifications

General

Display Type	LCD
Display Resolution	160 x 100 pixels
CPU	Motorola 68000
CPU Speed	16 MHz
RAM	256 KB
Flash ROM	2.7 MB
Programming Language	TI-BASIC, Assembly
Power Source	4 AAA batteries
Connectivity	I/O port
Dimensions	7.5 x 3.5 x 1 inches