QR Send vs Linear Algebra

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Linear Algebra turns any matrix problem into a teacher-style, step-by-step solution: what each step does, why it works, plus the final answer, a back-substitution check and exam tips. Free to download – every tool works and final answers are always free. Note: the app interface and step-by-step explanations are in Simplified Chinese. Matrices, formulas and answers are standard math notation. 39 SOLVER TOOLS • Exam essentials one tap away: determinant, inverse matrix, systems of linear equations, rank, eigenvalues & eigenvectors, diagonalization, quadratic form to canonical form, reduced row echelon form (RREF). • Organized by chapter: determinants & matrix operations, elementary row operations & rank, linear systems, vector sets, eigenvalues & quadratic forms, polynomials. • Advanced matrix theory: Jordan normal form, singular value decomposition (SVD), LU decomposition, Smith normal form, full-rank factorization, Moore–Penrose pseudoinverse, least squares, matrix norms and more. STEP-BY-STEP, LIKE A TEACHER • Every elementary row operation comes with an explanation, not just a wall of matrices. • Linear systems get the complete general solution (particular solution + basis of the null space); eigenvalue problems list all eigenvectors; diagonalization gives P and Λ. • The answer card sits on top, with automatic back-substitution checks and notes on common exam points and pitfalls. STUDY CARDS 39 topics organized as key formulas → solving method → worked example → typical exam questions → common mistakes, each tagged by how often it appears on exams. Jump from any card straight into the solver to try a problem. FREE AND FULL VERSION • Free: all tools, final answers always free, 3 full step-by-step solutions per day. • Full version (one-time purchase, not a subscription): unlimited access to every step and explanation, available on all your devices signed in with the same Apple ID, with Restore Purchases. RUNS ON YOUR DEVICE Problems are solved locally on your iPhone. Nothing is uploaded, and it works offline. PRIVACY & SUPPORT Privacy policy, FAQ and contact email are on the Support URL page below.