Question

Вычислить матрицу:

$left[begin{array}{ccc}11&3\10&9end{array}right]$ - 2

Answer 1

$left[begin{array}{ccc}11&3\ 10&9end{array}right] -2= left[begin{array}{ccc}11&3\ 10&9end{array}right] -2E,, boxed{=}$Где $E$ - единичная матрица.$boxed{=},, left[begin{array}{ccc}11&3\ 10&9end{array}right] -2 left[begin{array}{ccc}1&0\ 0&1end{array}right] = left[begin{array}{ccc}11&3\ 10&9end{array}right] - left[begin{array}{ccc}2cdot 1&2cdot 0\ 2cdot 0&2cdot 1end{array}right] =\ \ = left[begin{array}{ccc}11&3\ 10&9end{array}right] - left[begin{array}{ccc}2&0\ 0&2end{array}right] = left[begin{array}{ccc}11-2&3-0\ 10-0&9-2end{array}right] = left[begin{array}{ccc}9&3\ 10&7end{array}right]$