How do you find the determinant of ((-7, 0, 0, 3), (-5, -5, 0, 0), (0, -5, 0, 0), (-9, -4, 5, 2))?
1 Answer
Apr 30, 2016
Explanation:
´[[color(teal)(-7),0,color(orange)(0),3],[color(teal)(-5),-5,color(orange)(0),0],[color(teal)(0),-5,color(orange)(0),0],[color(teal)(-9),-4,color(orange)(5),2]]=
-> changing column1 with column3
=-[[0,0,-7,3],[0,-5,-5,0],[0,-5,0,0],[color(blue)(5),-4,-9,2]]
=-5*(-1)^(4+1)*[[0,-7,3],[-5,-5,0],[-5,0,0]]
=5*(-5)(-5)*[[0,-7,3],[1,1,0],[1,0,0]]
=125*[0-(3)]=-375