Linear Algebra and Geometry - a.y. 2024-2025
Office Hours
By appointment only
ada.boralevi@polito.itInstructors & Schedule:
Exercise Sessions:
Course Resources
Course Material
Suggested textbooks:
- G. Strang, Introduction to Linear Algebra, Wellesley-Cambridge Press, 2016.
- E. Carlini, LAG: the written exam, CLUT 2019.
Exam & Midterms Info
Course Schedule
| Title | Date | Content | References |
|---|---|---|---|
Lecture 1 Lecture | 2/25 | Matrices with real coefficients. Opposite and transpose of a matrix, properties. Square matrices: diagonal, triangular, symmetric, skew-symmetric. Linear algebra on a number field different from R. | 1.1, 1.2 |
Lecture 2-3 Lecture | 2/26 | Matrix addition and scalar multiplication: definition and properties, examples. Product of matrices: definition and examples. Properties of the product of matrices. Invertible matrices and their properties: inverse of the transpose and the product, examples. Linear equations and linear systems. Matrices associated to a linear system and matrix form. | 2.1, 2.2 |
Session on 3/3 Exercise | 3/3 | Exercise session with dr. Gollinucci: exercises and slides | |
Lecture 4 Lecture | 3/4 | Linear equations, linear systems, solutions, associated matrices, examples. Homogeneous and compatible systems. Elementary row operations, pivots, row-echelon form. Equivalent matrices and equivalent linear systems. Examples of Gauss reduction. Rank of a matrix. | 3.1, 3.2 |
Lecture 5-6 Lecture | 3/5 | Rank of a matrix. Examples and exercises on row reduction and rank computation. Solving a linear system: equivalent systems have equivalent associated matrices, Rouché-Capelli theorem, examples. Matrix equations and solutions: computation of inverse matrix via row reduction. Invertible matrices have maximal rank. Row and column rank, rank of the transpose. Submatrices, definition and examples. | 4.3 |
Lecture 7 Lecture | 3/11 | Determinants: submatrices, cofactors, examples. Determinant of the transpose matrix. Determinant and elementary row and column operations. Laplace expansion along rows and columns. Binet's theorem. Invertible matrices have nonzero determinant. Skew-symmetric odd size matrices have zero determinant. | 6.1, 6.2 |
Lecture 8-9 Lecture | 3/12 | Adjugate and cofactor matrix, computation of the inverse matrix using the adjugate, examples. Geometric vectors: segments, applied vectors, direction, orientation and length of a vector. Parallel and coplanar vectors. Cartesian systems of coordinates. Operations on vectors: sum and difference of vectors, multiplication by a scalar, properties and geometric interpretations. Quizzes on matrices and linear systems ( quizzes file 1 without solutions ). | 6.3 |
Session on 3/17 Exercise | 3/17 | Exercise session with dr. Gollinucci: exercises and slides | |
Lecture 10 Lecture | 3/18 | Normalization of a vector. Characterization of parallel and coplanar vectors through rank. Dot (scalar) product: definition, examples, properties. Dot product and angles: parallel and orthogonal vectors. | 7.5 |
Lecture 11-12 Lecture | 3/19 | Chauchy-Schwartz and triangle inequality. Orthogonal projection. Examples and exercises. Cross (vector) product: definition, geometric interpretation, properties, examples. Cross product and area of a triangle. Mixed product and volume of a tetrahedron. Some exercises on vectors. Introduction to parametric and cartesian equations of lines and planes. | 8.1, 8.2, 8.3 |
Lecture 13 Lecture | 3/25 | Parametric equations of lines and planes in space, examples. Relative position of two lines in space, examples. | 9.1, 9.2 |
Lecture 14-15 Lecture | 3/26 | Cartesian equations of planes in space; switching from parametric to Cartesian equation and backwards. Relative position of two planes in space and Cartesian equations of lines; switching from parametric to Cartesian equation and backwards. Relative position of linear objects in the space: a line and a plane and 2 lines. Examples and exercises. | 10.1, 10.2, 10.3 |
Session on 3/31 Exercise | 3/31 | Exercise session with dr. Gollinucci: exercises and slides | |
Lecture 16 Lecture | 4/1 | Exercises from worksheet 5. Distance of two sets, definition. Distance of a point from a plane, examples. | 11.1, part of 11.2 |
Lecture 17-18 Lecture | 4/2 | Distance of a point from a line, distance of a plane from another plane and from a line, distance between two lines, examples. Quizzes on lines and planes and distances ( quizzes file 3 without solutions ) | 11.2, 11.3, 11.4 |
Lecture 19-20 Lecture | 4/5 | Vector spaces and subspaces: definition, properties, examples. Union and intersection of subspaces, sum of subspaces, examples. Linear combinations. (Online lesson, you can find the recording on the teaching portal.). | 12.1, 12.2,12.3 |
Lecture 21-22 Lecture | 4/9 | Linear combinations, generators, finitely generated vector spaces: definitions and examples. Linearly dependent and independent vectors, examples. The discarding algorithm, examples. Bases and components with respect to a basis, examples. | 13.1, 13.2 |
Session on 4/12 Exam | 4/12 | 1st midterm | |
Session on 4/14 Exercise | 4/14 | Exercise session with dr. Gollinucci: exercises and slides | |
Lecture 23-24 Lecture | 4/16 | Extract a basis from a set of generators and complete a set of independent vectors to a basis. Number of vectors in a basis and dimension of a vector spaces, examples. Dimension of vector subspaces, examples. Grassmann formula, direct sum. Dimension and matrix rank: row and column space of a matrix. | 14.2 |
Lecture Holiday | Easter & Liberation day break 4/18-->4/25 | ||
Lecture 25 Exam | 4/29 | Linear maps: definition, examples, some properties. Definition of Kernel and Image. | 16.1, 16.2 |
Lecture 26-27 Lecture | 4/30 | Linear maps: kernel and image. Linear maps K^n-->K^m and their associated matrices, kernel, image and rank. Isomorphisms, isomorphic vector spaces, invertible matrices, examples. Linear maps for finitely generated vector spaces, examples. | 16.2, 16.3, 16.4 |
Session on 5/5 Exercise | 5/5 | Exercise session with dr. Gollinucci: exercises and slides | |
Lecture 28 Lecture | 5/6 | Linear maps for finitely generated vector spaces, matrix associated to a linear map: definition and examples. Dimension theorem: kernel, image and rank of the associated matrix. | 17.1, 17.2 |
Lecture 29-30 Lecture | 5/7 | Matrix associated to the composition of linear maps and to the inverse. Endomorphisms. Matrix of change of basis, examples. Eigenvalues, eigenvectors, eigenspaces: definition. Quizzes on vector spaces and subspaces. | 17.2, 17.3 |
Lecture 31 Lecture | 5/13 | Eigenvalues, eigenvectors, eigenspaces, characteristic polynomial: definition, properties, how to find them, examples. | 18.1, 18.2 |
Lecture 32-33 Lecture | 5/14 | Algebraic and geometric multiplicity of eigenvalues. Diagonalizable matrices. Similar matrices. Symmetric matrices are diagonalizable. Cayley-Hamilton theorem and eigenvalues of nilpotent matrices. Examples and exercises on diagonalization. | 19.1, 19.2, 19.3 |
Session on 5/19 Exercise | 5/19 | Exercise session with dr. Gollinucci: exercises and slides | |
Lecture 34 Lecture | 5/20 | Inner products: definition and examples. Cauchy-Schwartz inequality. Orthogonal and orthonormal sets and bases. Gram-Schmidt orthonormalization algorithm, introduction. | 20.1, 20.2 |
Lecture 35-36 Lecture | 5/21 | Orthogonal and orthonormal sets and bases. Gram-Schmidt orthonormalization algorithm, examples. Special and non-special orthogonal matrices. Orthonormal diagonalization for symmetric matrices, examples. Quizzes on linear maps, associated matrices, diagonalization ( quizzes file 5 without solutions ) | 20.2, 20.3, 20.4 |
Lecture 37 Lecture | 5/27 | Orthogonal matrices and rotations. Quadratic forms and symmetric matrices, positive/negative definite/semidefinite, indefinite forms. | 20.3 |
Lecture 38-39 Lecture | 5/28 | More on quadratic forms and their character of definition, with examples. Descartes' rule of signs. Conics in their canonical form: hyperbola, ellipse, parabola. Conics and rototranslations in the Euclidean plane. Reduction of a conic in its canonical form. | 21.2 |
Lecture Exercise | Exercise session with dr. Gollinucci: exercises and slides | ||
Session on 5/31 Exam | 5/31 | 2nd midterm | |
Lecture Holiday | Republic day 6/2 | ||
Lecture 40 Lecture | 6/3 | Classification of degenerate and non-degenerate conics through their associated matrices, examples. Introduction to quadric surfaces. Spheres: introduction and definition. | 23.2, 23.2 |
Lecture 41 Lecture | 6/4 | Spheres and circles in space: definitions and examples. Tangent plane and tangent lines to a sphere, intersection of two spheres, radical plane, examples. | 24.1, 24.2, 24.3 |
Lecture Exercise | Exercise session with dr. Gollinucci: exam simulation 3, slides | ||
Lecture 42 Exam | 6/6 | Exam simulation 4 | Simulation 4 (w/ solutions) |