Determinants Questions (2072)

Let $A = [a_{ij}]_{n \times n}$ where $a_{ij} = i^2 - j^2$. Then $A$ is
Let $A$ be a $3\times 3$ matrix of non-negative real numbers such that $A\begin{bmatrix}2\\2\\2\end{bmatrix}=4\begin{bmatrix}1\\1\\1\end{bmatrix}$. Then $(\det A)_{\max}$ is
$\text{tr}(A)$ is equal to
If \(S\) is the set of distinct values of \(b\) for which the following system of linear equations:\(x + y + z = 1\)\(x + ay + z = 1\)\(ax + by + z = 0\)has no solution, then \(S\) is
For what values of \(x\): \([1\quad 2\quad 1]\begin{bmatrix}1 & 2 & 0\\2 & 0 & 1\\1 & 0 & 2\end{bmatrix}\begin{bmatrix}0\\2\\x\end{bmatrix} = 0\,?
If $A = \begin{bmatrix} \cos\theta & -\sin\theta & 0 \\ \sin\theta & \cos\theta & 0 \\ 0 & 0 & 1 \end{bmatrix}$, then adj $A =$
If the system of equations $x+2y+3z=3$, $4x+3y-4z=4$, $8x+4y-\lambda z=9+\mu$ has infinitely many solutions, then the ordered pair $(\lambda,\mu)$ is equal to:
Let $A = \begin{pmatrix}1&2&2\\2&1&1\\2&2&1\end{pmatrix}$. If $A$ is a zero divisor of $x^2 - 4x - 5$, find $\text{Tr}(A^3)$.
In the matrix $A = \begin{bmatrix} 2 & 5 & 19 & 0 \\ 1 & 2 & 0 & 1 \\ 2 & 7 & \sqrt{3} & \sqrt{5} \end{bmatrix}$(i) The order of the matrix,(ii) The number of elements,(iii) Write the elements $a_{13}, a_{21}, a_{33}, a_{24}, a_{23}$.
If $A = \begin{bmatrix} 1 & 3 & 5 \\ 3 & 5 & 1 \\ 5 & 1 & 3 \end{bmatrix}$, then $\text{adj } A$ is equal to -
If $A = \begin{bmatrix} 2 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 2 \end{bmatrix}$, then $A^5 =$
If $A = \begin{bmatrix} -2 & -1 & 1 \\ -1 & 7 & 4 \\ 1 & -x & -3 \end{bmatrix}$ be symmetric matrix then find the value of $x$.
If $A$ and $B$ are matrices of order $m \times n$ and $n \times m$ respectively, then order of matrix $B^T(A^T)^T$ is -
Obtain the inverse of the following matrix using elementary operations $A = \begin{bmatrix} 0 & 1 & 2 \\ 1 & 2 & 3 \\ 3 & 1 & 1 \end{bmatrix}$.
Let $\alpha$ be a solution of $x^2 + x + 1 = 0$, and for some $a$ and $b$ in $\mathbb{R}$, $$\begin{bmatrix} 4 & a & b \end{bmatrix} \begin{bmatrix} -1 & -1 \\ 2 & -2 \\ -14 & -8 \end{bmatrix} = \begin{bmatrix} 0 & 0 \end{bmatrix}$$ If $\frac{4}{\alpha^2} + \frac{m}{\alpha} + n = 3$, then $m + n$ is equal to
70. If \(y = \sin(mx)\) and \(y_n = \dfrac{d^n y}{dx^n}\), then the determinant \[\begin{vmatrix} y & y_1 & y_2 \\ y_3 & y_4 & y_5 \\ y_6 & y_7 & y_8 \end{vmatrix} =\] ______.
Let $a \in \mathbb{R}$ and $A$ be a matrix of order $3 \times 3$ such that $\det(A) = -4$ and $A + I = \begin{bmatrix} 1 & a & 1 \\ 2 & 1 & 0 \\ a & 1 & 2 \end{bmatrix}$, where $I$ is the identity matrix of order $3 \times 3$. If $\det((a+1)\operatorname{adj}((a-1)A)) = \frac{2^m}{3^n}$, $m, n \in \{0, 1, 2, \ldots, 20\}$, then $m + n$ is equal to:
If $A = \begin{bmatrix} 0 & -1 & 2 \\ 2 & -2 & 0 \end{bmatrix}$, $B = \begin{bmatrix} 0 & 1 \\ 1 & 0 \\ 1 & 1 \end{bmatrix}$ and $M = AB$, then $M^{-1}$ is equal to
Let $I$ be the identity matrix of order $3 \times 3$ and for the matrix $A = \begin{bmatrix} \lambda & 2 & 3 \\ 4 & 5 & 6 \\ 7 & -1 & 2 \end{bmatrix}$, $|A| = -1$. Let $B$ be the inverse of the matrix $\text{adj}(A \cdot \text{adj}(A))$. Then $|\lambda B + I|$ is equal to ______
Let $A$ be a $3 \times 3$ matrix such that $|\text{adj}(\text{adj}(\text{adj}A))| = 81$. If $S = \{n \in \mathbb{Z} : (|\text{adj}(\text{adj}A)|)^{2(n-1)} = |A|^{2(3n^2-5n-4)}\}$, then $\sum_{n \in S} |n^2 + n|$ is equal to
If all rows multiplied by k, determinant becomes:
If \(A\) is identity matrix, then det(A\)^{-1}) equals:
The number of singular matrices of order 2 , whose elements are from the set {2, 3, 6, 9} is
Choose the correct answer
15. Consider \(a_{33}\) it is the biggest number in the \(3 \times 3\) sub matrix formed by top left corner so minimum value of \(a_{33}\) is 9. Now again consider \(a_{33}\) it is the smallest number in \((n-3)(n-3)\) sub matrix formed by bottom left corner of the main matrix. If \(b_j\) denotes the number of elements in the set \(\{a_{jj} : j^2 \leq a_{jj} \leq n^2 - (n-j+1)^2 + 1\}\), find \(\sum_{j=1}^{n} b_j\).
If $A$ and $B$ are two square matrices of order $3 \times 3$ which satisfy $AB = A$ and $BA = B$, then $(A + B)^9$ is equal to
Let $A_k=[a_{ij}]$ be square matrix of order 3 with $a_{ij}=(i-j)^k$ for all $i,j\in\{1,2,3\}$. Determinant value of $|A_1+A_3+A_5+\cdots+A_{2023}|$ equals
Solve the system $x+y+z=6$, $x-y+z=2$, $2x+y-z=1$ using matrix method.
Let \(A = \begin{bmatrix} a & b \\ b & a \end{bmatrix}\) and \(A^2 = \begin{bmatrix} \alpha & \beta \\ \beta & \alpha \end{bmatrix}\). Then which of the following is correct?
If \(B B' = A^{-1} A' (A^{-1} A')' \), and simplifying, which of the following equals \(BB'\)?
Let $A = \begin{pmatrix}1&2&2\\2&1&1\\2&2&1\end{pmatrix}$. If $A$ is a zero divisor of $x^2 - 4x - 5$, find $\text{Tr}(A^3)$.
If $A = \begin{bmatrix} 2 & 0 & 0 \\ 2 & 2 & 0 \\ 2 & 2 & 2 \end{bmatrix}$, then $adj(adj A)$ is equal to -
If $A$ and $B$ are matrices of order $m \times n$ and $n \times m$ respectively, then order of matrix $B^T(A^T)^T$ is -
Let $A = \begin{pmatrix} \cos(\pi/5) & -\sin(\pi/5) \\ \sin(\pi/5) & \cos(\pi/5) \end{pmatrix}$ and $B = \begin{pmatrix} 1 & 0 \\ 0 & -1 \end{pmatrix}$. If $\displaystyle\sum_{r=1}^{4}\bigl(B^2 - B\cdot A^{9r} - A^r\cdot B + A^{10r}\bigr) = \begin{pmatrix} a & b \\ c & d \end{pmatrix}$, then $a^{10} + b^{10} + c^{10} + d^{10} =$
Let $A$ and $B$ be $3\times 3$ invertible matrices such that $A^2B=BA$ and $P=A^{-1}$. Then the value of $P^3B^3A^3$ is:
Let $A$ and $B$ be $3\times 3$ invertible matrices such that $A^2B=BA$ and $P=A^{-1}$. Then the value of $P^3B^3A^3$ is:
The least value of the product xyz for which the determinant \(\begin{vmatrix} x & 1 & 1 \\ 1 & y & 1 \\ 1 & 1 & z \end{vmatrix}\) is non-negative, is
Given matrix $A = \begin{bmatrix} 1 & x & 1 \\ x & 2 & y \\ 1 & y & 3 \end{bmatrix}; B = \begin{bmatrix} 3 & -3 & z \\ -3 & 2 & -3 \\ z & -3 & 1 \end{bmatrix}$. Obtain $x, y, z$ if the matrix $AB$ is symmetric.
If \(a^2 + b^2 + c^2 = -2\) and \[f(x) = \begin{vmatrix} (1+a^2)x & (1+b^2)x & (1+c^2)x \\ (1+a^2)x & (1+b^2)x & (1+c^2)x \\ (1+a^2)x & (1+b^2)x & (1+c^2)x \end{vmatrix}\] then \(f(x)\) is a polynomial of degree
If \(\det(A)\)=k, then det(A\)^3A⁻^3) equals:
Let $T=\{\alpha_1,\alpha_2,\beta\}$ be the 3 distinct roots of $x^2+x-1=0$ (note: a quadratic has at most 2 roots; here the set $T$ includes specific values). For a $3\times 3$ matrix $M=(a_{ij})$, let $R_i=a_{i1}+a_{i2}+a_{i3}$ and $C_j=a_{1j}+a_{2j}+a_{3j}$. Match entries in List-I with List-II: P) Number of $M$ with all entries in $T$ such that $R_i=C_j=0$ for all $i,j$ Q) Number of symmetric $M$ with all entries in $T$ such that $C_j=0$ for all $j$ R) Skew-symmetric $M$ with $a_{ij}\in T$ for $i>j$ — number of solutions to $M(x,y,z)^T=(-a,a,0)^T$ S) $M$ with all entries in $T$, $R_i=0$ for all $i$ — absolute value of $\det(M)$ List-II: 1)1, 2)12, 3)∞, 4)6, 5)0
**Paragraph:** Let $\alpha,\beta,\gamma$ be real roots of $x^3+ax^2+bx+c=0$ ($a,b,c\in\mathbb{R}$, $a,b\neq 0$). If the system $\alpha u+\beta v+\gamma w=0$, $\beta u+\gamma v+\alpha w=0$, $\gamma u+\alpha v+\beta w=0$ has non-trivial solution, then the minimum value of $x(3x+2a)+b+1$ is: A) $5$\quad B) $3$\quad C) $1$\quad D) $0$
If the system of linear equations\(x + ay + z = 3\)\(x + 2y + 2z = 6\)\(x + 5y + 3z = b\)has no solution, then
Let $A = \begin{pmatrix} \cos(\pi/5) & -\sin(\pi/5) \\ \sin(\pi/5) & \cos(\pi/5) \end{pmatrix}$ and $B = \begin{pmatrix} 1 & 0 \\ 0 & -1 \end{pmatrix}$. If $\displaystyle\sum_{r=1}^{4}\bigl(B^2 - B\cdot A^{9r} - A^r\cdot B + A^{10r}\bigr) = \begin{pmatrix} a & b \\ c & d \end{pmatrix}$, then $a^{10} + b^{10} + c^{10} + d^{10} =$
Let $T=\{\alpha_1,\alpha_2,\beta\}$ be the 3 distinct roots of $x^2+x-1=0$ (note: a quadratic has at most 2 roots; here the set $T$ includes specific values). For a $3\times 3$ matrix $M=(a_{ij})$, let $R_i=a_{i1}+a_{i2}+a_{i3}$ and $C_j=a_{1j}+a_{2j}+a_{3j}$. Match entries in List-I with List-II: P) Number of $M$ with all entries in $T$ such that $R_i=C_j=0$ for all $i,j$ Q) Number of symmetric $M$ with all entries in $T$ such that $C_j=0$ for all $j$ R) Skew-symmetric $M$ with $a_{ij}\in T$ for $i>j$ — number of solutions to $M(x,y,z)^T=(-a,a,0)^T$ S) $M$ with all entries in $T$, $R_i=0$ for all $i$ — absolute value of $\det(M)$ List-II: 1)1, 2)12, 3)∞, 4)6, 5)0
**Paragraph:** Let $\alpha,\beta,\gamma$ be real roots of $x^3+ax^2+bx+c=0$ ($a,b,c\in\mathbb{R}$, $a,b\neq 0$). If the system $\alpha u+\beta v+\gamma w=0$, $\beta u+\gamma v+\alpha w=0$, $\gamma u+\alpha v+\beta w=0$ has non-trivial solution, then the minimum value of $x(3x+2a)+b+1$ is: A) $5$\quad B) $3$\quad C) $1$\quad D) $0$
**Paragraph (continued):** Consider the system $x+2y-3z=a$; $2x+6y-11z=b$; $x-2y+7z=c$. Then the system: A) has a unique solution when $5a=2b+c$ B) has infinite number of solutions when $5a=2b+c$ C) has no solution for all $a,b,c$ D) has a unique solution for all $a,b,c$
If $P = \begin{bmatrix} \frac{\sqrt{3}}{2} & \frac{1}{2} \\ -\frac{1}{2} & \frac{\sqrt{3}}{2} \end{bmatrix}$, $A = \begin{bmatrix} 1 & 1 \\ 0 & 1 \end{bmatrix}$ and $Q = PAP^T$ and $x = P^T Q^{2005} P$, then $x$ is equal to -
$\begin{bmatrix} 1 & -\tan \theta/2 \\ \tan \theta/2 & 1 \end{bmatrix} \begin{bmatrix} 1 & \tan \theta/2 \\ -\tan \theta/2 & 1 \end{bmatrix}^{-1}$ is equal to -
Let \(\phi(x) = \begin{vmatrix} x+a & x+b & x+a-c \\ x+b & x+c & x+1 \\ x+c & x+d & x+b-d \end{vmatrix}\) and \(\int_0^2 \phi(x)\,dx = -16\), where \(a, b, c\) and \(d\) are in AP, then the common difference of the AP is equal to