Define the determinant of an n x n matrix inductively
let A be an n x n matrix DET A = IAI which can be written as the SUMMATION (-1)^n a1j1a2j2...anjn
the sum is taken over all possible permutations of the elements the sign is positive if n is even and negative if odd
the number of permutations is n factorial
sorry its hard to explain on this message board
try to make sense of the example given on this website it may help http://www.ltcconline.net/greenl/courses/203/MatricesApps/determinants.htm
Thanks so much for helping. What sign are you referring to? "the sign is positive if n is even and negative if odd"
Just opened the link. Thank you!
the sign depends on wether the permutation is even/odd in a 3x3 matrice your permutations will be (1,23) (1,3,2) (3,1,2) etc the first number would mean the first number in row 1 the 2 means the second number in row 2 and the 3 means the 3rd number in row 3 multiply them together and add up all answers
but for (1,3,2) this means multiply teh first number in row 1, the third number in row 2 and the second number in row 3
try the website you should be able to get some marks on that question good luck!
Thank you!
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