Engineering Mathematics I

Linear Algebra


Module II: Linear Algebra. This unit builds the foundations of matrix algebra, systems of equations, special matrices, eigen analysis and basic numerical techniques. Emphasis is on exam focused concepts.


Algebra of Matrices

  • Addition, scalar multiplication and matrix multiplication.
  • Properties include associativity, distributivity and non-commutativity.
  • Transpose and conjugate transpose operations.

Diagram: matrix-algebra.png


Rank and Inverse of a Matrix

  • Rank is the maximum number of linearly independent rows or columns.
  • Determined using row echelon form or determinant methods.
  • Inverse exists only if det(A) ≠ 0.

Diagram: rank-echelon.png


Hermitian, Skew Hermitian and Unitary Matrices

  • Hermitian: A = A†.
  • Skew Hermitian: A = −A†.
  • Unitary: A†A = I.
  • Important for stability and orthogonality in linear systems.

Eigenvalues and Eigenvectors

  • Defined by A x = λ x.
  • Obtained from characteristic equation det(A − λI) = 0.
  • Used in system stability, diagonalization and modal analysis.

Systems of Linear Equations and Consistency

  • Ax = b form.
  • Consistent if rank(A) = rank(A b).
  • Unique solution if rank(A) = rank(A b) = n.
  • Infinite solutions if rank(A) = rank(A b) < n.

Numerical Methods for Solving Systems

  • Gauss elimination and Gauss Jordan elimination.
  • Gauss Seidel iterative method.

Diagram: gauss-methods.png


Vector Spaces and Linear Transformations

  • Vector space: set with vector addition and scalar multiplication.
  • Basis: minimal set of linearly independent vectors that span the space.
  • Linear transformations preserve vector addition and scalar multiplication.