If A = 1- 2202 - 33- 24, then A . adj (A

Subject

Mathematics

Class

JEE Class 12

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

1.

The solution of tan-1x + 2cot-1x = 2π3 is

  • - 13

  • 13

  • - 3

  • 3


2.

The value of sin2cos-153 is

  • 53

  • 253

  • 459

  • 259


3.

If A = 1- 1121- 3111, 10B = 422- 50α1- 23 and B is the inverse of A, then the value of α is

  • 2

  • 0

  • 5

  • 4


Advertisement

4.

If A = 1- 2202 - 33- 24, then A . adj (A) is equal to

  • 511151115

  • 500050005

  • 800080008

  • 000000000


C.

800080008

Given, A = 1- 2202 - 33- 24C11 = 8 - 6 = 2, C21 = - - 8 + 4 = 4, C31 = 6 - 4 = 2C12 = - 0 + 9 = - 9, C22 = 4 - 6 = - 2, C32 = - - 3 - 0 = 3,C13 = 0 - 6 = - 6, C23 = - - 2 + 6 = - 4, C33 = 2 - 0 = 2adj A = 2- 9 - 64- 2- 4232T 242- 9- 23- 6- 42           = 800080008


Advertisement
Advertisement
5.

If f : R  R is defined by f(x) = lxl, then

  • f-1(x) = - x

  • f-11x

  • the function f-1(x) does not exist

  • f-1x = 1x


6.

If A = 0x16x5 709xis singular, then the possible values of x are

  • 0, 12, - 12

  • 0, 1, - 1

  • 0, 4, - 4

  • 0, 5, - 5


7.

The value of xpqpxqpqx is

  • x(x - p)(x - q)

  • (x - p)(x - q)(x + p + q)

  • (p - q)(x - q)(x - p)

  • pq(x - p)(x - q)


8.

The range in which y = - x2 + 6x - 3 is increasing is

  • x < 3

  • x > 3

  • 7 < x < 8

  • 5 < x < 6


Advertisement
9.

OA and OB are two roads enclosmng an angle of 120°. X and Y start from 'O' at the same time. X travels along OA with a speed of 4 km/h and Y travels along OB with a speed of 3 km/h.The rate at which the shortest distance between X and Y is increasing after 1 h is

  • 37 km /h

  • 37 km/h

  • 13 km/h

  • 13 km/h


10.

If the function f(x) = 1 - cosxx2, x  0k,                  x = 0 is continuous at x = 0, then the value of k is

  • 1

  • 0

  • 12

  • - 1


Advertisement