If AX = B and A is a nonsingular square matrix, which expression gives X?
Correct answer: C. X = A⁻¹B
- A. X = AB
- B. X = BA
- C. X = A⁻¹B
- D. X = B⁻¹A
Explanation
Premultiplying AX = B by A⁻¹ gives A⁻¹AX = A⁻¹B. Since A⁻¹A is the identity matrix, X = A⁻¹B.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
Practise Simultaneous Equations and Matrices
30 free Simultaneous Equations and Matrices MCQs from Quantitative Methods, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Quantitative Methods questions like this
Quantitative Methods is on this paper prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for it.
More Simultaneous Equations and Matrices questions
For which values of k is the matrix [[k, 2], [8, k]] singular?
What is the solution of the system x + y + z = 6, x + y - z = 2, and x - y + z = 4?
What is the inverse of the matrix [[2, 1], [3, 2]]?
The augmented matrix of a system contains a row [0 0 0 | 5]. What does this indicate?
If the coefficient determinant of two simultaneous linear equations is nonzero, what does this imply?
If 2x + 3y = 13 and x + y = 5, what is the value of x?