Question

Помогите пожалуйста Математика

Answer 1

Ответ:

$1\ \ M_{32}=\left|\begin{array}{ccc}-2&5\\0&3\end{array}\right|=-6-0=-6\\\\\\2)\ \ C=\left|\begin{array}{ccc}2&5\\-3&2\end{array}\right|\cdot \left|\begin{array}{ccc}3&-4&8\\0&5&1\end{array}\right|=\left|\begin{array}{ccc}6&17&21\\-9&12&-24\end{array}\right|\\\\\\c_{12}+c_{13}+c_{21}+c_{23}=17+21-9-24=5$

$3)\ \ \left|\begin{array}{ccc}lgx+5&2\\lgx&-1\end{array}\right|=-2\ \ \ \ ,\ \ \ \ \ \ x>0\ ,\\\\\\-lgx-5-2lgx=-2\\\\-3lgx=3\ \ ,\ \ lgx=-1\ \ ,\ \ \ x=10^{-1}\ \ ,\ \ x=\dfrac{1}{10}$