EnglishUP PCS (Pre) 1995 & 1999
Q321.The matrices A, B, C are such that the addition and multiplication occuring in the statements given below are valid. The incorrect statement is:
Correct answer: A(B+C) = AB+AC
Q322.If A and B are square matrices of the same order such that A2 = I = B2 I being the unit matrix, then:
Correct answer: is true
Q323.The rank of the matrix 0 3 1 2 4 0 3 6 9 12 0 5 10 15 20 is
Correct answer: 1
Q324.The determinant 1 0 0 2 a a 2 1 1 is zero for:
Correct answer: every value of a
Q325.The value of the determinant 1 2 3 4 1 3 6 10 1 4 10 20 1 5 15 35 is:
Correct answer: 1
Q326.The diagonal elements of a skew-symmetric matrix are
Correct answer: zero elements
Q327.The system of linear equations x+2y+3z = kx, 3x+y+2z = ky, 2x+3y+z = kz has a non–zero solution when k equals
Correct answer: 6
Q328.If 0 1 2 1 2 3 A = 0, B = -2, C = 1 3 1 1 2 are matrices, then the order of (5A–3B) C is:
Correct answer: 3×1
Q329.The value of the determinant 1 2 3 47 1 3 6 10 1 4 10 20 1 5 15 a is
Correct answer: 35
Q330.If 1 1 A 1 1 − = − and 1 2 B 3 2 = are two matrices, then:
Correct answer: AB ≠ BA
Q331.The rank of the matrix 1 2 3 2 4 1 1 2 7 − − − − is:
Correct answer: 2
Q332.If A and B are matrices of the same order, then (A + B)2 = A2 + B2 + 2AB is possible if
Correct answer: AB = BA
Q333.The value of the determinant 3 5 1 7 9 16 1 4 5 30 1 14 6 20 50 1 is:
Correct answer: 1
Q334.If 0 1 0 -2 1 3 A = and B = 2 3 1 2 1 -1 are two matrices then:
Correct answer: AB and BA exist but AB≠BA
Q335.The inverse of the matrix cos θ sin θ -sin θ cos θ is:
Correct answer: cos θ -sin θ/sin θ cos θ
Q336.If 0 1 A = 1 2 and 1 B = 2 then AB is equal to:
Correct answer: 2/5
Q337.If ω is a cube root of unity then the value of the determinant: 2 a b c a b c a b c ω is:
Correct answer: None of these
Q338.The rank of the matrix 1 -3 2 -3 9 -6 2 -6 4 is equal to:
Correct answer: 1
Q339.If 1 A = 2 and B =[2,3] are two matrices then (AB)–1 is:
Correct answer: does not exist
Q340.If I3 is the identity matrix of order 3, then [I3]–1 is equal to
Correct answer: I3