PRE CALCULUS Matrices and Vectors

Question 1

What is the determinant of the matrix [[3, 1], [2, 4]]?

Accepted Answer

10

Answer

14

Answer

8

Answer

12

Question 2

Which operation is NOT defined for matrices A and B?

Accepted Answer

A + B when dimensions differ

Answer

A × B when A is 2×3 and B is 3×2

Answer

Scalar multiplication of A

Answer

A − A

Question 3

What is the result of multiplying a 2×3 matrix by a 3×4 matrix?

Accepted Answer

2×4 matrix

Answer

3×3 matrix

Answer

2×3 matrix

Answer

6×4 matrix

Question 4

What is the identity matrix for 2×2 multiplication?

Accepted Answer

[[1,0],[0,1]]

Answer

[[0,1],[1,0]]

Answer

[[1,1],[1,1]]

Answer

[[0,0],[0,0]]

Question 5

If vector u = ⟨3, −4⟩, what is |u|?

Accepted Answer

5

Answer

7

Answer

1

Answer

√7

Question 6

What does the dot product u · v = 0 indicate about vectors u and v?

Accepted Answer

They are perpendicular

Answer

They are parallel

Answer

They are equal

Answer

They are unit vectors