Intro to Matrices

You may choose to watch this video and create notes for INB 17 (Intro to Matrices) & INB 19 (Matrix Multiplication)

Or use the following videos and outline.

INB 17
Intro to Matrix Operations

I. Watch video 0-3:25 and stop.

Pause throughout to jot any notes, examples you wish to record.

a. What is a matrix?
b. How do you define the size?
c. In order to add or subtract what must be true?
d. Explain how to add or subtract two matrices.
e. Why do you think they call it scalar multiplication?

III. Practice these 4 problems.

And check, then record results on green organizer.

INB 19
Matrix Multiplication

I. Watch video from 3:26 to 9:04.

Pause as needed to jot down any notes and examples.

II. Complete these 6 questions.
a. When can 2 matrices be multiplied?
b. How can we tell the dimensions of our answer matrix?
c.  Give dimensions of 2 matrices that can be multiplied.
d.  What is the dimension of their answer matrix?
e.  Give dimensions of 2 matrices that cannot be multiplied.
f. Multiply Practice (handout from class).

Sample Notes for INB 19

INB 21
Evaluating Determininants
2×2 Matrix (2:45)
3×3 Matrix (3:29)
Finding Area video.
Copy examples from videos into notes.

1. Give an example of a square matrix. Why is it called a square matrix?
2. Show how to find the determinatn of a 2 x 2 matrix.
3. To find the determinant of a 2×2 square matrix, does it matter if you take bc-ad instead of ad-bc? Why/Why not?
4. How can you use the determinant of a matrix to find the area of a triangle?
5. If you apply a scalar of 2 to your triangle coordinates matrix, how does it affect the determinant value?

INB 23
Why Inverses?
Enigma Code video.

Video for Finding 2×2 inverses Notes/Examples. (4:24)

INB 25
Using Technology in Class Notes