CAIE FP1 2015 June — Question 11 EITHER

Exam BoardCAIE
ModuleFP1 (Further Pure Mathematics 1)
Year2015
SessionJune
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
Topic3x3 Matrices
TypeRange space basis and dimension
DifficultyChallenging +1.8 This question requires understanding of range space, basis, dimension, and the rank-nullity theorem. Part (i) needs row reduction to find rank. Part (ii) requires showing linear independence and span. Parts (iii-iv) involve deeper conceptual understanding of vector spaces and complements. While systematic, it demands multiple advanced techniques and conceptual maturity beyond standard A-level, typical of Further Maths linear algebra.
Spec4.03a Matrix language: terminology and notation4.03b Matrix operations: addition, multiplication, scalar4.03c Matrix multiplication: properties (associative, not commutative)4.03l Singular/non-singular matrices4.03r Solve simultaneous equations: using inverse matrix

The linear transformation \(\mathrm { T } : \mathbb { R } ^ { 4 } \rightarrow \mathbb { R } ^ { 4 }\) is represented by the matrix \(\mathbf { M }\), where $$\mathbf { M } = \left( \begin{array} { r r r r } 1 & 2 & 3 & 4 \\ 1 & - 1 & 2 & 3 \\ 1 & - 3 & 3 & 5 \\ 1 & 4 & 2 & 2 \end{array} \right)$$ The range space of T is denoted by \(V\).
  1. Determine the dimension of \(V\).
  2. Show that the vectors \(\left( \begin{array} { l } 1 \\ 1 \\ 1 \\ 1 \end{array} \right) , \left( \begin{array} { r } 2 \\ - 1 \\ - 3 \\ 4 \end{array} \right) , \left( \begin{array} { l } 3 \\ 2 \\ 3 \\ 2 \end{array} \right)\) are a basis of \(V\). The set of elements of \(\mathbb { R } ^ { 4 }\) which do not belong to \(V\) is denoted by \(W\).
  3. State, with a reason, whether \(W\) is a vector space.
  4. Show that if the vector \(\left( \begin{array} { l } x \\ y \\ z \\ t \end{array} \right)\) belongs to \(W\) then \(x + y \neq z + t\).

The linear transformation $\mathrm { T } : \mathbb { R } ^ { 4 } \rightarrow \mathbb { R } ^ { 4 }$ is represented by the matrix $\mathbf { M }$, where

$$\mathbf { M } = \left( \begin{array} { r r r r } 
1 & 2 & 3 & 4 \\
1 & - 1 & 2 & 3 \\
1 & - 3 & 3 & 5 \\
1 & 4 & 2 & 2
\end{array} \right)$$

The range space of T is denoted by $V$.\\
(i) Determine the dimension of $V$.\\
(ii) Show that the vectors $\left( \begin{array} { l } 1 \\ 1 \\ 1 \\ 1 \end{array} \right) , \left( \begin{array} { r } 2 \\ - 1 \\ - 3 \\ 4 \end{array} \right) , \left( \begin{array} { l } 3 \\ 2 \\ 3 \\ 2 \end{array} \right)$ are a basis of $V$.

The set of elements of $\mathbb { R } ^ { 4 }$ which do not belong to $V$ is denoted by $W$.\\
(iii) State, with a reason, whether $W$ is a vector space.\\
(iv) Show that if the vector $\left( \begin{array} { l } x \\ y \\ z \\ t \end{array} \right)$ belongs to $W$ then $x + y \neq z + t$.

\hfill \mbox{\textit{CAIE FP1 2015 Q11 EITHER}}