1. Determinants
Get out your notes and be ready to complete a warm-up on your new purple sheet.

2. Warm-Up
Evaluate each Determinant
1 −5 3 − −4

3. A couple of reminders
To find a Second-Order Determinant 𝑎 𝑏 𝑐 𝑑 =𝑎𝑑−𝑏𝑐 Difference of the product of the diagonals. To find a Third-Order Determinant 𝑎 𝑏 𝑐 𝑑 𝑒 𝑓 𝑔 ℎ 𝑖 =𝑎 𝑒 𝑓 ℎ 𝑖 −𝑏 𝑑 𝑓 𝑔 𝑖 −𝑐 𝑑 𝑒 𝑔 ℎ Or, we can use diagonals.

4. Example of a Third-Order Determinant
Evaluate the Determinant
−1 4 5 −1 3 −5 −2 −4 −4
-30
-20 16
−1 4 −1 3 −2 −4 12 40 20
Add the bottom products and subtract the top products.
− −30 − −20 −16
=106

5. Closure
Evaluate the Determinant
−1 2 0 −3 −2 3 −4 −4 3