lecture revision notes for the 2nd year course module MATH0047 - Advanced Linear Algebra. Shortened and simplified to use as revision summary for exams
Definition a permutation of a set of numbers I n is an
arrangement of the numbers in some order without
commissions or repetitions
,the possible permutations of set 1,213 is
112,3 1 3,2 2 1,3 2,311 3 1,2 3,211
there are n permutations of the set where n is the
number values
of different
Inversion Occurs in a permutation when a
larger number
precedes a smaller one
If O 1 2,3 there are 0 inversions
If o 2,1 3 there is 1 inversion
O 3,2 1 there are 3 inversions
If
Sign The sign of a permutation is defined as
sign o 1 if there is an even number
inversions of
sign o 1 if there is an odd number of
inversions
An elementary product of matrix
Elementary product is a product of n entries
an nxn
such that
there is one each
row and exactly
column entry from
signed elementary product
sign o x elementary product
Determinant A Square Matrix
of
diet A Ee sign o Aloe Anon
this is the sum
of all signed elementary products
, Co factor Expansion
obtain the minor of a certain Ali by removing
column i and j and computing
entry
the determinant the
entries of
remaining
i e
A 11 11
minor of ALI I A22A33 A23A32
co
factor C1 tix A II
Determinant Z cofactor x
entry value
it
El 1 Ai Ali in the raw column that
we are observing
Note
there is zero column in the matrix the determina
If
will be
a
zero
row
always
det A det AT
upper triangle A square matrix is upper triangular it the
entries above the main diagonal art zeros i e
1
Lower A matrix is lower the
triangle square
entries below the
triangular
main diagonal are if zeros i e
I
The determinants of an upper triangular and lower triangular
matrix is the product the entries on the main diagonal
of
A matrix is invertible if the determinent is a non zero
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller gajendranragulram. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £10.49. You're not tied to anything after your purchase.