The number of symmetric matrices of order 3, with all the entries from the set {0,1,2,3,4,5,6,7,8,9} is :
Mathematicsmatrices-and-determinants2023hard
Let A=[105111]. If B=[1−12−1]A[−11−21], then the sum of all the elements of the matrix \sum_\limits{n=1}^{50} B^{n} is equal to
Mathematicsmatrices-and-determinants2023medium
If the system of linear equations
7x+11y+αz=135x+4y+7z=β175x+194y+57z=361
has infinitely many solutions, then α+β+2 is equal to :
Mathematicsmatrices-and-determinants2023easy
x+1xxxx+λxxxx+λ2=89(103x+81), then λ,3λ are the roots of the equation :
Mathematicsmatrices-and-determinants2023medium
Let A be a 2×2 matrix with real entries such that A′=αA+I, where α∈R−{−1,1}. If det(A2−A)=4, then the sum of all possible values of α is equal to :
Mathematicsmatrices-and-determinants2023medium
If A=5!6!7!15!6!7!6!7!8!7!8!9!, then ∣adj(adj(2A))∣ is equal to :
Mathematicsmatrices-and-determinants2023medium
If A is a 3 × 3 matrix and ∣A∣=2, then ∣3adj(∣3A∣A2)∣ is equal to :
Mathematicsmatrices-and-determinants2023hard
For the system of linear equations
2x−y+3z=53x+2y−z=74x+5y+αz=β,
which of the following is NOT correct?
Mathematicsmatrices-and-determinants2023medium
If A=[1λ510],A−1=αA+βI and α+β=−2, then 4α2+β2+λ2 is equal to :
Mathematicsmatrices-and-determinants2023medium
Let S be the set of all values of θ∈[−π,π] for which the system of linear equations
x+y+3z=0−x+(tanθ)y+7z=0x+y+(tanθ)z=0
has non-trivial solution. Then \frac{120}{\pi} \sum_\limits{\theta \in \mathrm{s}} \theta is equal to :
Mathematicsmatrices-and-determinants2023medium
Let A=21012−10−12. If ∣adj(adj(adj2A))∣=(16)n, then n is equal to :
Mathematicsmatrices-and-determinants2023medium
Let P=[23−212123],A=[1011] and Q=PAPT. If PTQ2007P=[acbd], then 2a+b−3c−4d equal to :
Mathematicsmatrices-and-determinants2023medium
If the system of equations
x+y+az=b2x+5y+2z=6x+2y+3z=3
has infinitely many solutions, then 2a+3b is equal to :
Mathematicsmatrices-and-determinants2023easy
Let A=[aij]2×2, where aij=0 for all i,j and A2=I. Let a be the sum of all diagonal elements of A and b=∣A∣. Then 3a2+4b2 is equal to :
Mathematicsmatrices-and-determinants2023medium
Let P be a square matrix such that P2=I−P. For α,β,γ,δ∈N, if Pα+Pβ=γI−29P and Pα−Pβ=δI−13P, then α+β+γ−δ is equal to :
Mathematicsmatrices-and-determinants2023medium
For the system of equations
x+y+z=6x+2y+αz=10x+3y+5z=β, which one of the following is NOT true?
Mathematicsprobability2023medium
Two dice are thrown independently. Let A be the event that the number appeared on the 1st die is less than the number appeared on the 2nd die, B be the event that the number appeared on the 1st die is even and that on the second die is odd, and C be the event that the number appeared on the 1st die is odd and that on the 2nd is even. Then :
Mathematicsprobability2023medium
In a binomial distribution B(n,p), the sum and the product of the mean and the variance are 5 and 6 respectively, then 6(n+p−q) is equal to :
Mathematicsprobability2023medium
A bag contains 6 balls. Two balls are drawn from it at random and both are found to be black. The probability that the bag contains at least 5 black balls is :
Mathematicsprobability2023hard
If an unbiased die, marked with −2,−1,0,1,2,3 on its faces, is thrown five times, then the probability that the product of the outcomes is positive, is :