[tex]a) e b) A:\left[\begin{array}{ccc}3&4\\2&1\end{array}\right]=(3.1)-(4.2)=3-8=>det(A)=-5\\\\c) B: \left[\begin{array}{ccc}2&1&0\\-3&1&2\\2&4&5\end{array}\right]\\=[(2.1.5)+(-3.4.0)+(1.2.2)]-[(0.1.2)+(2.4.2)+(-3.1.5)]\\=[10+0+4]-[0+16-15]=14-1=>det(B)=13[/tex]
[tex]B^t: \left[\begin{array}{ccc}2&-3&2\\1&1&4\\0&2&5\end{array}\right]\\\\=[(2.1.5)+(-3.4.0)+(1.2.2)]-[(2.1.0)+(4.2.2)+(-3.1.5)]\\=[10+0+4]-[0+16-15]=14-1=>det(B^t)=13[/tex]
