If and is the angle between the two non-zero column vectors such that for some scalar

MATHEMATICS · Single correct · IB Diploma Programme · Mathematics: Applications and Interpretation · Number and Algebra · Number and Algebra

Problem

A=\begin{bmatrix}1&2\\-1&4\end{bmatrix}

and

\theta

is the angle between the two non-zero column vectors

x

such that

Ax=\lambda x

for some scalar

\lambda

, then

9\sec^2\theta

is equal to (1) 13 (2) 12 (3) 11 (4) 10