yaitu
120
Pembahasan:
3A – 2B
= 3⎛3 3⎞ _ 2⎛–1 2⎞
⎝2 4⎠ ⎝4 1⎠
= ⎛9+2 9–4⎞
⎝6–8 12–2⎠
= ⎛11 5⎞
⎝–2 10⎠
det (3A – 2B) = 11.10 – 5(–2)
= 110 + 10
= 120
yaitu
120