MATH 3120 — Linear Algebra
UPenn MATH 3120, Spring 2026.
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daniel.krashen+lalg@gmail.com
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Lecture 1 (January 14, 2026)
: Introductions
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Lecture 2 (January 21, 2026)
: Reduced row echelon form, spaces of vectors
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Lecture 3 (January 28, 2026)
: Rank and number of solutions, introduction to matrix algebra
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Lecture 4 (February 2, 2026)
: Matrix algebra
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Lecture 5 (February 4, 2026)
: Linear transformations and matrices
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Lecture 6 (February 9, 2026)
: Matrix multiplication is composition, intro to matrix factorization
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Lecture 7 (February 11, 2026)
: Matrix factorization, subspaces, image, rank, nullity
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Lecture 8 (February 16, 2026)
: Spanning and independent sets, geometry and projections
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Exam 1 practice sheet (February 18, 2026)
:
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Lecture 9 (March 2, 2026)
: More orthogonality, introduction to determinants
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Lecture 10 (March 4, 2026)
: Determinants, transposes
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Lecture 11 (March 16, 2026)
: Determinants, abstract vector spaces
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Lecture 12 (March 18, 2026)
: Linear transformations between abstract vector spaces, isomorphisms, inner products
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Lecture 13 (March 23, 2026)
: Least squares approximations and applications
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Exam 2 practice sheet (February 18, 2026)
:
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Lecture 14 (April 1, 2026)
: Rank-nullity, matrices from linear transformations
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Lecture 15 (April 6, 2026)
: Eigenvalues and eigenvectors
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Lecture 16 (April 8, 2026)
: Symmetric matrices have real eigenvalues
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Lecture 17 (April 13, 2026)
: The (real) spectral theorem / principal axes theorem
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Lecture 18 (April 15, 2026)
: Worksheet practice (#7)
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Lecture 19 (April 19, 2026)
: Singular value decomposition
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