Chapter 8.4, Problem 63E

To determine

To calculate: The determinant of the matrix,

  $\begin{array}{ccc}3& 8& -7\\ 0& -5& 4\\ 8& 1& 6\end{array}$

With help of graphing utility.

Answer to Problem 63E

The determinant of the matrixis $-126$ .

Explanation of Solution

Given information:

The matrix,

  $\begin{array}{ccc}3& 8& -7\\ 0& -5& 4\\ 8& 1& 6\end{array}$

Formula used:

The matrix capabilities of graphing utility.

Calculation:

Consider the matrix,

  $\begin{array}{ccc}3& 8& -7\\ 0& -5& 4\\ 8& 1& 6\end{array}$

The steps to evaluate the determinant of the matrix with help of Ti-83 calculator are as follows:

Step 1: Press $\boxed{\text{2nd}}$ key.

Step 2: Press $\boxed{x^{-1}}$ key.

Step 3: Use the right arrow key to move to $\boxed{\text{EDIT}}$ option and press $\boxed{\text{ENTER}}$ key.

Step 4: Change the dimension to $3\times 3$ and press $\boxed{\text{ENTER}}$ key.

Step 5: Enter the matrix values row wise and after each entry press $\boxed{\text{ENTER}}$ key.

Step 6: Press $\boxed{\text{2nd}}$ key and then $\boxed{\text{MODE}}$ key.

Step 7: Press $\boxed{\text{2nd}}$ key and then $\boxed{x^{-1}}$ key.

Step 8: Use the right arrow key to move to $\boxed{\text{MATH}}$ option and press $\boxed{\text{ENTER}}$ key.

Step 9: Press $\boxed{\text{2nd}}$ key and then $\boxed{x^{-1}}$ key.

Step 10: Press the $\boxed{\text{ENTER}}$ key and close the parenthesis.

The result obtained on the screen below isprovided below

  

Thus, the determinant of the matrixis $-126$ .