Ответ:
3
Пошаговое объяснение:
![Det=\left|\begin{array}{cccc}5&4&1&3\\3&2&1&1\\2&1&1&4\\1&3&-2&2\end{array}\right| =5*\left|\begin{array}{ccc}2&1&1\\1&1&4\\3&-2&2\end{array}\right|-3*\left|\begin{array}{ccc}4&1&3\\1&1&4\\3&-2&2\end{array}\right| +2*\left|\begin{array}{ccc}4&1&3\\2&1&1\\3&-2&2\end{array}\right| -1*\left|\begin{array}{ccc}4&1&3\\2&1&1\\1&1&4\end{array}\right|](https://tex.z-dn.net/?f=Det%3D%5Cleft%7C%5Cbegin%7Barray%7D%7Bcccc%7D5%264%261%263%5C%5C3%262%261%261%5C%5C2%261%261%264%5C%5C1%263%26-2%262%5Cend%7Barray%7D%5Cright%7C%20%3D5%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D2%261%261%5C%5C1%261%264%5C%5C3%26-2%262%5Cend%7Barray%7D%5Cright%7C-3%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D4%261%263%5C%5C1%261%264%5C%5C3%26-2%262%5Cend%7Barray%7D%5Cright%7C%20%2B2%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D4%261%263%5C%5C2%261%261%5C%5C3%26-2%262%5Cend%7Barray%7D%5Cright%7C%20-1%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D4%261%263%5C%5C2%261%261%5C%5C1%261%264%5Cend%7Barray%7D%5Cright%7C)
![5*\left|\begin{array}{ccc}2&1&1\\1&1&4\\3&-2&2\end{array}\right|=5*((2*1*2+1*4*3+1*1*(-2))-(1*1*3+1*1*2+2*4*(-2)))=5*((4+12-2)-(3+2-16))=5*(14+11)=5*25=125\neq 0](https://tex.z-dn.net/?f=5%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D2%261%261%5C%5C1%261%264%5C%5C3%26-2%262%5Cend%7Barray%7D%5Cright%7C%3D5%2A%28%282%2A1%2A2%2B1%2A4%2A3%2B1%2A1%2A%28-2%29%29-%281%2A1%2A3%2B1%2A1%2A2%2B2%2A4%2A%28-2%29%29%29%3D5%2A%28%284%2B12-2%29-%283%2B2-16%29%29%3D5%2A%2814%2B11%29%3D5%2A25%3D125%5Cneq%200)
Отсюда, ранг матрицы не меньше 3!
![3*\left|\begin{array}{ccc}4&1&3\\1&1&4\\3&-2&2\end{array}\right|=3*((4*1*2+1*4*3+3*1*(-2))-(3*1*3+1*1*2+4*4*(-2)))=3*((8+12-6)-(9+2-32))=3*(14+21)=3*35=105](https://tex.z-dn.net/?f=3%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D4%261%263%5C%5C1%261%264%5C%5C3%26-2%262%5Cend%7Barray%7D%5Cright%7C%3D3%2A%28%284%2A1%2A2%2B1%2A4%2A3%2B3%2A1%2A%28-2%29%29-%283%2A1%2A3%2B1%2A1%2A2%2B4%2A4%2A%28-2%29%29%29%3D3%2A%28%288%2B12-6%29-%289%2B2-32%29%29%3D3%2A%2814%2B21%29%3D3%2A35%3D105)
![2*\left|\begin{array}{ccc}4&1&3\\2&1&1\\3&-2&2\end{array}\right|=2*((4*1*2+1*1*3+3*2*(-2))-(3*1*3+1*2*2+4*1*(-2)))=2*((8+3-12)-(9+4-8))=2*(-1-5)=2*(-6)=-12](https://tex.z-dn.net/?f=2%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D4%261%263%5C%5C2%261%261%5C%5C3%26-2%262%5Cend%7Barray%7D%5Cright%7C%3D2%2A%28%284%2A1%2A2%2B1%2A1%2A3%2B3%2A2%2A%28-2%29%29-%283%2A1%2A3%2B1%2A2%2A2%2B4%2A1%2A%28-2%29%29%29%3D2%2A%28%288%2B3-12%29-%289%2B4-8%29%29%3D2%2A%28-1-5%29%3D2%2A%28-6%29%3D-12)
![1*\left|\begin{array}{ccc}4&1&3\\2&1&1\\1&1&4\end{array}\right|=1*((4*1*4+1*1*1+3*2*1)-(3*1*1+1*2*4+4*1*1))=(16+1+6)-(3+8+4)=23-15=8](https://tex.z-dn.net/?f=1%2A%5Cleft%7C%5Cbegin%7Barray%7D%7Bccc%7D4%261%263%5C%5C2%261%261%5C%5C1%261%264%5Cend%7Barray%7D%5Cright%7C%3D1%2A%28%284%2A1%2A4%2B1%2A1%2A1%2B3%2A2%2A1%29-%283%2A1%2A1%2B1%2A2%2A4%2B4%2A1%2A1%29%29%3D%2816%2B1%2B6%29-%283%2B8%2B4%29%3D23-15%3D8)
Тогда
![Det=125-105+(-12)-8=125-125=0](https://tex.z-dn.net/?f=Det%3D125-105%2B%28-12%29-8%3D125-125%3D0)
и отсюда следует, что ранг матрицы меньше 4.
Значит, ранг матрицы равен 3.
Ответ:
=321
Пошаговое объяснение:
букву n заменяем на число 147, и получается пример 147+62+46+66=321
1) составляем пропорцию 1/7= х/100
Х= 1*100/7=14.3%
2) 40%= 0,8 кг меди, следовательно олова 1,2 кг.
Чтобы получить 16% меди нужно добавить 3 кг олова
Также составляем пропорцию 0,8/16=х/100
Х= 5кг (из них 0,8 меди, 1,2 олова изначально и +3 кг добавить)
Первое решение на фото!
2.
<span>6.4x-5,56x +3,84=10,14
6.4х-5.56х=10.14-3.84
0.84х=6.3
х=6.3/0.84
х=7.5
</span>