Salick Academy

Vectors and Matrices II

No calculator

Original questions written at exam standard. Work each one before you open the solution.

Difficulty
Question 1 Foundation
Find the determinant of (5243)\begin{pmatrix} 5 & 2 \\ 4 & 3 \end{pmatrix}.
Question 2 Foundation
Explain why (3612)\begin{pmatrix} 3 & 6 \\ 1 & 2 \end{pmatrix} has no inverse.
Question 3 Standard
OA=a\overrightarrow{OA} = \mathbf{a} and OB=b\overrightarrow{OB} = \mathbf{b}. Write AB\overrightarrow{AB} in terms of a\mathbf{a} and b\mathbf{b}.
Question 4 Standard
Find the inverse of (2132)\begin{pmatrix} 2 & 1 \\ 3 & 2 \end{pmatrix}.
Question 5 Stretch
MM is the midpoint of ABAB, where OA=a\overrightarrow{OA} = \mathbf{a} and OB=b\overrightarrow{OB} = \mathbf{b}. Find OM\overrightarrow{OM}.
Question 6 Stretch
Find the image of (4,1)(4, -1) under the transformation with matrix (0110)\begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix}, and name the transformation.