Question

1_calcule os determinantes abaixo:
me ajudemmmmm​

Answer 1

a) Det=14

$\left|\begin{array}{ccc}1&6&9\\5&2&4\\7&0&1\end{array}\right|=1.2.1+6.4.7+5.0.9-(9.2.7+6.5.1+4.0.1)=$

$=2+168+0-(126+30+0)=170-156=14$

b) Det=136

$\left|\begin{array}{ccc}2&0&4\\7&8&2\\2&5&5\end{array}\right|=2.8.5+0.2.2+7.5.4-(4.8.2+0.7.5+2.5.2)=$

$=80+0+140-(64+0+20)=220-84=136$

c) Det=2

$\left|\begin{array}{ccc}1&2&3\\2&5&6\\2&5&8\end{array}\right| =1.5.8+2.6.2+2.5.3-(3.5.2+2.2.8+6.5.1)=$

$=40+24+30-(30+32+30)=94-92=2$