If f : R ---->R defined by f(x) = x2 + 1, then values of f -1 (17) and f -1(-3) are respectively
A. | {Ø}, (4, - 4) |
B. | {3,-3},{Ø} |
C. | {Ø},{3,-3} |
D. | {4,-4},Ø |
Option: D Explanation : Click on Discuss to view users comments. |
In a beauty contest, half the number of experts voted for Mr. A and two thirds voted for Mr. B. 10 voted for both and 6 did not vote for either. How many experts were there in all ?
A. | 18 |
B. | 36 |
C. | 24 |
D. | None of these |
Option: C Explanation : Click on Discuss to view users comments. |
Let n(A) denotes the number of elements in set A. If n(A) =p and n(B) = q, then how many ordered pairs (a, b) are there with a ∈ A and b ∈ B ?
A. | p2 |
B. | p x q |
C. | p + q |
D. | 2 pq |
Option: B Explanation : Click on Discuss to view users comments. |