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Matrices — Question 127

Original QCE Vault practice · 5 marks

Q127 · Practice questionTechnology-freeComplex familiar5 marks

QUESTION 127 (5 marks)

Let

A=\begin{pmatrix}2&1\\1&1\end{pmatrix}

.

a)

Find

A\begin{pmatrix}3\\-1\end{pmatrix}

.

[1 mark]

b)

Find

A^{-1}

.

[2 marks]

c)

Find the vector

v

such that

Av=\begin{pmatrix}7\\4\end{pmatrix}

.

[2 marks]

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