Finding Inverses of Matrices

What size is this matrix?

• 2x2

• 2x3

• 3x2

• 1x6

What is the formula for the determinant of a 2x2 matrix?

• ad-bc

• ab-cd

• ad+bc

• (a+d)(b+c)

What is the determinant of this matrix?

• 5

• -5

• 0

• -12

Will this matrix have an inverse?

• Yes

• No

• Unable to Determine

Calculate the determinant

• 0
• -15
• -70
• 10

Calculate the Determinant

• det = 2

• det = -2

• det = -64

• det = 64

What is a₂₃

• 14

• 4

• 1

• 3

Which of the following matrices do NOT have an inverse? 
*Inverse=
                 ¹∕detA × ⌈d  −b⌉                                      ⌊−c  a⌋

• [1  2]
  [3  4]
• [6  0]
  [4  2]
• ⌈6  3⌉
  ⌊4  2⌋

What is the inverse of this matrix?

• _{(1/25)  (-4/25)
  (3/25)  (13/25)}
• _{(1/5)  (-4/5)
  (3/5)  (13/5)}
• _{(6/25)  (-2/25)
  (2/25)  (9/25)}
• _{(1/150)  (-4/150)
  (3/150)  (13/150)}

Which of the following is the inverse of the matrix A= 
⌈3  0⌉
⌊0  2⌋
*Inverse=
                 ¹∕detA × ⌈d  −b⌉                                      ⌊−c  a⌋

• [1/2    0]
  [0    1/3]
• [-3  0]
  [0  -2]
• ⌈1/3   0⌉
  ⌊0   1/2⌋
• [2  0]
  [0  3]