Matrices on the TI-83
10-10 in the TI-83 Guidebook

The TI series calculator performs numerous matrix operations. This example shows Gaussian Elimination.   The function rref is a easy way to find the reduce-row echelon form of any size matrix. (up to 99 rows)  It has many applications in this book.

Press matrx.jpg (911 bytes) . Press arr_rt.jpg (739 bytes) arr_rt.jpg (739 bytes) to display the MATRX EDIT menu.  Press 1 to select 1:[A].  
Press 2 enter.jpg (983 bytes) 2 enter.jpg (983 bytes) to define a 34 matrix.  (3 rows, 4 columns)  The rectangular cursor indicates the current element.  Ellipses (...) indicate additional columns beyond the screen.
Press -2 enter.jpg (983 bytes) 4 enter.jpg (983 bytes)  for the first row.
Press -3 enter.jpg (983 bytes) 7 enter.jpg (983 bytes) for the second row.
 
Press 2nd.jpg (858 bytes) [QUIT] to return to the home screen.  If necessary press clear.jpg (1014 bytes) to clear the home screen.
wpe151.jpg (2755 bytes) Press matrx.jpg (911 bytes) 1 to select 1:[A] from the MATRX NAMES menu.  Press xinv.jpg (781 bytes) enter.jpg (983 bytes) .

You can leave your matrix in fractional form.
Press matrx.jpg (911 bytes) 1 to select 1:[A] from the MATRX NAMES menu.
Press xinv.jpg (781 bytes)  math.jpg (945 bytes) 1 to select 1: Frac from the MATH menu.

 

Experiment using exponents with matrices.

Press matrx.jpg (911 bytes) 1 to select 1:[A] from the MATRX NAMES menu.
Press carot.jpg (773 bytes)  2  .    This is the same as [A] [A] .
Press carot.jpg (773 bytes)  3  .     This is the same as [A] [A]  [A] .
wpe166.jpg (4161 bytes)