Q. 8 - Precalculus Enhanced with Graphing Utilities

Question

Find the value of the determinant.

$\left|\begin{array}{cc}8& -3\\ 4& 2\end{array}\right|$

Step-by-Step Solution

Answer

$\left|\begin{array}{cc}8& -3\\ 4& 2\end{array}\right|=28$

Step 1. Given information

We have been given:

$\left|\begin{array}{cc}8& -3\\ 4& 2\end{array}\right|$

We have to find the value of this determinant. 

Step 2. Use formula D = a b c d = a ⋅ d - c ⋅ b .

$$\begin{gathered} \left|\begin{array}{cc}8& -3\\ 4& 2\end{array}\right|=8\times 2-4\times (-3) \\ =16+12 \\ =28 \end{gathered}$$