Odpowiedź:
zad. 1
[tex]x * y = \frac{x + y}{c + 1}[/tex]
x = 2, y = 6
[tex]2 * 6 = \frac{2 + 6}{c + 1}\\[/tex]
[tex]12 = \frac{8}{c + 1}[/tex]
12 (c + 1) = 8
12c + 12 = 8
12c = -4
[tex]c = -\frac{4}{12} = -\frac{1}{3}[/tex]
zad. 2
[tex]\left[\begin{array}{cccc}1&2&3&4\\2&1&0&0\\3&5&1&1\\c&2&1&0\end{array}\right][/tex]
det = 1*1*1*0 + 2*0*1*c + 3*0*3*2 + 4*2*5*1 - 4*0*5*c - 0*1*2*1 - 1*1*2*2-0*3*1*3=
= 0 + 0 + 0 + 40 - 0 - 0 - 4 - 0 = 36
