Finance

1. Using a matrix method find the solution of the following system of linear
equations.
X+3X+5X=7
2X+4X+6X=8
4X+11X+18X=C
When C=25, what happens to your solution system.
Wehn C=0?

2. Find the inverse of the matrix
1 1 1
2 3 2
3 2 2

3. Calculate the determinant of the following matrix
1 -2 2 1
-1 3 -3 2
2 4 1 -1
-2 -3 5 3

5. A factory has the following total profit function
total profit π=-2q^3 - 15q^2 + 1800q - 168
where q is the level of the production. Find the level of production that will maximize the total profit.