Matrices Questions with Solutions
A matrix is a rectangular arrangement of numbers in rows and columns. This topic covers types of matrices (square, diagonal, scalar, identity, symmetric and skew-symmetric), matrix operations (addition, scalar multiplication and matrix multiplication), the transpose, determinants and their properties, minors and cofactors, the adjoint, and the inverse of a matrix. It also covers solving systems of linear equations using the inverse method and elementary row and column transformations. Remember that matrix multiplication is not commutative, so AB need not equal BA, and that the inverse exists only when the determinant is not zero. Useful results include |AB| = |A||B|, (AB)^-1 = B^-1 A^-1, and |kA| = k^n |A| for a matrix of order n. These properties solve many questions without heavy calculation. Practise the matrices questions below, each with a step-by-step solution.
- Q21.
If x, y, z are distinct real numbers and , then find xyz.
A. 1B. -1C. 2D. -2mediumAsked in NIMCET 2019View solution › - Q22.
The system of equations , , has infinitely many solutions if
A. B. C. D.mediumAsked in NIMCET 2024View solution › - Q23.
Consider the matrix . The sum of all the entries of the matrix is
A. B. C. D.hardAsked in NIMCET 2025View solution › - Q24.
Let and be two square matrices of the same order satisfying and respectively, where is the identity matrix. Then the inverse of the matrix is
A. B. C. D.hardAsked in NIMCET 2025View solution › - Q25.
If , and are the three cube roots of 27, then the determinant of the matrix is
A. 1B. 0C. D.mediumAsked in NIMCET 2025View solution ›