- Chapter 1: Matrices and Systems of Equations
- Chapter 1.1: Systems of Linear Equations
- Chapter 1.2: Row Echelon Form
- Chapter 1.3: Matrix Arithmetic
- Chapter 1.4: Matrix Algebra
- Chapter 1.5: Elementary Matrices
- Chapter 1.6: Partitioned Matrices
- Chapter 2: Determinants
- Chapter 2.1: The Determinant of a Matrix
- Chapter 2.2: Properties of Determinants
- Chapter 2.3: Additional Topics and Applications
- Chapter 3: Vector Spaces
- Chapter 3.1: Definition and Examples
- Chapter 3.2: Subspaces
- Chapter 3.3: Linear Independence
- Chapter 3.4: Basis and Dimension
- Chapter 3.5: Change of Basis
- Chapter 3.6: Row Space and Column Space
- Chapter 4: Linear Transformations
- Chapter 4.1: Definition and Examples
- Chapter 4.2: Matrix Representations of Linear Transformations
- Chapter 4.3: Similarity
- Chapter 5: Orthogonality
- Chapter 5.1: The Scalar Product in Rn
- Chapter 5.2: Orthogonal Subspaces
- Chapter 5.3: Least Squares Problems
- Chapter 5.4: Inner Product Spaces
- Chapter 5.5: Orthonormal Sets
- Chapter 5.6: The GramSchmidt Orthogonalization Process
- Chapter 5.7: Orthogonal Polynomials
- Chapter 6: Eigenvalues
- Chapter 6.1: Eigenvalues and Eigenvectors
- Chapter 6.2: Systems of Linear Differential Equations
- Chapter 6.3: Diagonalization
- Chapter 6.4: Hermitian Matrices
- Chapter 6.5: The Singular Value Decomposition
- Chapter 6.6: Quadratic Forms
- Chapter 6.7: Positive Definite Matrices
- Chapter 6.8: Nonnegative Matrices
- Chapter 7: Numerical Linear Algebra
- Chapter 7.1: Floating-Point Numbers
- Chapter 7.2: Gaussian Elimination
- Chapter 7.3: Pivoting Strategies
- Chapter 7.4: Matrix Norms and Condition Numbers
- Chapter 7.5: Orthogonal Transformations
- Chapter 7.6: The Eigenvalue Problem
- Chapter 7.7: Least Squares Problems
Linear Algebra with Applications 8th Edition - Solutions by Chapter
Full solutions for Linear Algebra with Applications | 8th Edition
Upper triangular systems are solved in reverse order Xn to Xl.
A matrix can be partitioned into matrix blocks, by cuts between rows and/or between columns. Block multiplication ofAB is allowed if the block shapes permit.
Change of basis matrix M.
The old basis vectors v j are combinations L mij Wi of the new basis vectors. The coordinates of CI VI + ... + cnvn = dl wI + ... + dn Wn are related by d = M c. (For n = 2 set VI = mll WI +m21 W2, V2 = m12WI +m22w2.)
When random variables Xi have mean = average value = 0, their covariances "'£ ij are the averages of XiX j. With means Xi, the matrix :E = mean of (x - x) (x - x) T is positive (semi)definite; :E is diagonal if the Xi are independent.
Elimination matrix = Elementary matrix Eij.
The identity matrix with an extra -eij in the i, j entry (i #- j). Then Eij A subtracts eij times row j of A from row i.
Jordan form 1 = M- 1 AM.
If A has s independent eigenvectors, its "generalized" eigenvector matrix M gives 1 = diag(lt, ... , 1s). The block his Akh +Nk where Nk has 1 's on diagonall. Each block has one eigenvalue Ak and one eigenvector.
lA-II = l/lAI and IATI = IAI.
The big formula for det(A) has a sum of n! terms, the cofactor formula uses determinants of size n - 1, volume of box = I det( A) I.
Left inverse A+.
If A has full column rank n, then A+ = (AT A)-I AT has A+ A = In.
Linear combination cv + d w or L C jV j.
Vector addition and scalar multiplication.
= Xl (column 1) + ... + xn(column n) = combination of columns.
Multiplicities AM and G M.
The algebraic multiplicity A M of A is the number of times A appears as a root of det(A - AI) = O. The geometric multiplicity GM is the number of independent eigenvectors for A (= dimension of the eigenspace).
A directed graph that has constants Cl, ... , Cm associated with the edges.
Outer product uv T
= column times row = rank one matrix.
Ps = pascal(n) = the symmetric matrix with binomial entries (i1~;2). Ps = PL Pu all contain Pascal's triangle with det = 1 (see Pascal in the index).
Permutation matrix P.
There are n! orders of 1, ... , n. The n! P 's have the rows of I in those orders. P A puts the rows of A in the same order. P is even or odd (det P = 1 or -1) based on the number of row exchanges to reach I.
Similar matrices A and B.
Every B = M-I AM has the same eigenvalues as A.
Singular matrix A.
A square matrix that has no inverse: det(A) = o.
Triangle inequality II u + v II < II u II + II v II.
For matrix norms II A + B II < II A II + II B II·
Vandermonde matrix V.
V c = b gives coefficients of p(x) = Co + ... + Cn_IXn- 1 with P(Xi) = bi. Vij = (Xi)j-I and det V = product of (Xk - Xi) for k > i.
Volume of box.
The rows (or the columns) of A generate a box with volume I det(A) I.