8/8 - 数学演習II

$\cdot\left( \begin{array}{rr} 1 & 4\\ 2 & 3 \end{array} \right) ?$
$\cdot\left( \begin{array}{rr} \cos\theta & -\sin\theta\\ \sin\theta & \cos\theta \end{array} \right) ?$
$\cdot\left( \begin{array}{rrr} 1&2&2 \\ 1&2&-1 \\ -1&1&4 \end{array} \right) ?$

次の行列は(準)正定値か、(準)不定値か?