Answer:
130
Step-by-step explanation:
You want the determinant of the matrix ...
![\left[\begin{array}{ccc}4&3&2\\-3&1&5\\-1&-4&3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%263%262%5C%5C-3%261%265%5C%5C-1%26-4%263%5Cend%7Barray%7D%5Cright%5D)
One way to figure it is as the difference between the sum of products of the down-diagonals and the sum of products of the up-diagonals:
D = (4)(1)(3) +(3)(5)(-1) +(2)(-3)(-4) -(-1)(1)(2) -(-4)(5)(4) -(3)(-3)(3)
= 12 -15 +24 +2 +80 +27
D = 130
The determinant of the coefficient matrix is 130.
_____
Many scientific and graphing calculators and web sites can perform this calculation for you.
Step-by-step explanation:
<B is the right angle
<A is acute
<C is acute
<D is obtuse
-5i/2i. is the answer because all you have to do is add the -5 and the i.
I think that this is a combination problem. From the given, the 8 students are taken 3 at a time. This can be solved through using the formula of combination which is C(n,r) = n!/(n-r)!r!. In this case, n is 8 while r is 3. Hence, upon substitution of the values, we have
C(8,3) = 8!/(8-3)!3!
C(8,3) = 56
There are 56 3-person teams that can be formed from the 8 students.