Question

o determinante da matriz

3 5 1
0 2 1
-1 0 4

Answer 1

$A = \left[\begin{array}{ccc}3&5&1\\0&2&1\\-1&0&4\end{array}\right] \\\\\\ \left[\begin{array}{ccc}3&5&1\\0&2&1\\-1&0&4\end{array}\right] \left\begin{array}{cc}3&5\\0&2\\-1&0\end{array}\right\\\\\\det(A) = (3*2*4) + (5*1*(-1)) + (1*0*0) - (5*0*4) - (3*1*0) - (1*2*(-1))\\det(A) = 24 -5 + 0 - 0 - 0 + 2\\det(A) = 24 - 5 + 2\\det(A) = 26 - 5\\det(A) = 21$

Com isso, o determinante da matriz é 21.