Math 220 (Fall 2013): Lecture Notes and Videos on Introductory Linear Algebra

Copyright: I (Bala Krishnamoorthy) hold the copyright for all lecture scribes/notes, documents, and other materials including videos posted on these course web pages. These materials might not be used for commercial purposes without my consent.

Scribes from all lectures so far (as a single big file)

Lec Date Topic(s) Scribe Video
1 Aug 20 syllabus, intro to mymathlab.com, 2D example (2 linear equations in 2 variables), graphical solution Scb1 Vid1
2 Aug 22 Gaussian elimination, augmented matrix, elementary row operations (EROs), \( \begin{bmatrix} 0 & 0 & \cdots & 0 & | & {\bf \star}\neq 0 \end{bmatrix}\) -- inconsistent system Scb2 Vid2
3 Aug 27 nonzero row, leading entry, echelon form and reduced echelon form, row reduction Scb3 Vid3
4 Aug 29 symbolic notation for echelon form, basic and free variables, parametric form of solutions, vectors, linear combination, span, Scb4 Vid4
5 Sep   3 pictures of span in 2D & 3D, span all of \( \mathbb{R}^n \), matrix form \( A \mathbf{x} = \mathbf{b} \) Scb5 Vid5
6 Sep   5 \( A \mathbf{x} = \mathbf{b} \) consistent \( \forall \mathbf{b}\) iff \(A\) has a pivot in every row, homogenous system, trivial solution, parametric vector form of solutions Scb6 Vid6
7 Sep 10 Solutions to \(A\mathbf{x} = \mathbf{b}\) in relation to those of \(A\mathbf{x} = \mathbf{0}\), linear independence (LI) of vectors, special case of LI for a single vector Scb7 Vid7
8 Sep 12 LI of two vectors, with \( \mathbf{0} \), \(\{\mathbf{v}_1,\dots,\mathbf{v}_n\}\) is LD when \( \mathbf{v}_i \in \mathbb{R}^m\) and \(n > m\), (matrix) transformations, (co)domain, image, range Scb8 Vid8
9 Sep 17 review of problems from Sections 1.4, 1.5, and 1.7 (as we are slowing down:-) Scb9 Vid9
10 Sep 19 linear transformations (LT), preserve vector addition and scalar multiplication, matrix of an LT Scb10 Vid10
11 Sep 24 matrix of an LT, geometric transformations - rotation, reflection, shear, projection, onto and one-to-one transformations Scb11 oops:-(
12 Sep 26 problems on matrix of LT, onto and one-to-one LTs, onto iff pivot in every row, 1-to-1 iff pivot in every column Scb12 Vid12
13 Oct   1 review of practice midterm exam Scb13 Vid13
14 Oct   3 midterm exam
15 Oct   8 class canceled
16 Oct 10 By Prof. McDonald: matrix multiplication, power and transpose of a matrix; notes from Prof. McDonald Scb16 NA
17 Oct 15 inverse of a matrix, inverse of \(2 \times 2 \) matrix, determinant, properties of matrix inverses Scb17 Vid17
18 Oct 17 inverting \( n \times n \) matrix, \( [ A | I] \longrightarrow [ I | A^{-1} ]\), using properties of inverses, invertible matrix theorem (IMT) Scb18 Vid18
19 Oct 22 invertible matrix theorem (IMT) - statements (a)-(l), problems using IMT Scb19 Vid19
20 Oct 24 subspaces - of \( \mathbb{R}^2 \), generated by \(\{ \mathbf{v_1},\dots,\mathbf{v_p}\}\); column and null spaces of \(A\) - \( \operatorname{Col} A, \operatorname{Nul} A\), basis for a subspace Scb20 Vid20
21 Oct 29 By Prof. McDonald: bases for \( \operatorname{Col} A\),\( \operatorname{Nul} A\), dimension of a subspace, rank, rank theorem, IMT (contd..); Prof. McDonald's notes Scb21 NA
22 Oct 31 class canceled
23 Nov  5 coordinates of \({\bf x}\) in a basis \(\mathcal{B}\): \( [{\bf x}]_{\mathcal{B}} \), more on dimension and rank, determinant of a \( 3 \times 3\) matrix, expand along Row 1 Scb23 Vid23
24 Nov  7 Computer project, intro to MATLAB, \(n \times n\) determinant by expanding along Row 1, cofactor expansion along any row/column Scb24 Vid24
25 Nov 12 \(\operatorname{det}\) of triangular matrix, \(\operatorname{det}(A)\) using EROs, \(A^{-1}\) exists \(\Leftrightarrow \operatorname{det}(A) \neq 0\), \(\operatorname{det}(A^T) = \operatorname{det}(A)\), \(\operatorname{det}(AB) = \operatorname{det}(A)\operatorname{det}(B)\) Scb25 Vid25
26 Nov 14 \(\operatorname{det}(B^{-1}AB) = \operatorname{det}(A)\) when \(\operatorname{det}(B) \neq 0\), eigenvalues and eignevectors, \((A^T = A) \Rightarrow \) all eignvalues of \(A\) are real Scb26 oops:-(
27 Nov 19 testing eigenvalues/eigenvectors, eigenspace, eigenvalues of triangular matrices are diagonal entries, all rows of \(A\) adding to \(s\) Scb27 Vid27
28 Nov 21 characteristic polynomial & equation, multiplicity of eigenvalue, similar matrices, EROs and eigenvalues, Matlab for project Scb28 Vid28
29 Dec   3 scalar (or dot) product of vectors, length of vector, orthogonal vectors and sets, orthogonal basis, orthogonal projection Scb29 Vid29
30 Dec   5 write vector \(\mathbf{y}\) as \(\mathbf{y_u} + \mathbf{v}\), where \(\mathbf{y_u} \in\) span\(\{\mathbf{u}\}\) and \(\mathbf{v} \perp \mathbf{y_u}\), review for final exam Scb30 Vid30


Last modified: Fri Dec 06 08:27:24 PST 2013