Relations and Functions Class 12 MCQs Questions with Answers

1. The function f : A → B defined by f(x) = 4x + 7, x ∈ R is

2.  
Let * be a binary operation on set Q – {1} defind by a * b = a + b – ab : a, b ∈ Q – {1}. Then * is

3. Let f : [0, ∞) → [0, 2] be defined by f(x)=2x/1+x, then f is

4. Which one of the following relations on R is an equivalence relation?

5. Consider the binary operation * on a defined by x * y = 1 + 12x + xy, ∀ x, y ∈ Q, then 2 * 3 equals

6.  
If A, B and C are three sets such that A ∩ B = A ∩ C and A ∪ B = A ∪ C. then

7. Let g(x) = x2 – 4x – 5, then

8. A = {1, 2, 3} which of the following function f: A → A does not have an inverse function

9. If f : R → R and g : R → R defined by f(x) = 2x + 3 and g(x) = x2 + 7, then the value of x for which f(g(x)) = 25 is

10. Let us define a relation R in R as aRb if a ≥ b. Then R is

11. Let R be the relation “is congruent to” on the set of all triangles in a plane is

12. Let P = {(x, y) | x² + y² = 1, x, y ∈ R]. Then, P is

13. Let f: |2, ∞) → R be the function defined by f(x) – x² – 4x + 5, then the range of f is

14. Let us define a relation R in R as aRb if a ≥ b. Then R is

15. Let * be a binary operation on set of integers I, defined by a * b = a + b – 3, then find the value of 3 * 4.

16.  
Let R be the relation “is congruent to” on the set of all triangles in a plane is

17. Let f(x) = x2 – x + 1, x ≥ 12, then the solution of the equation f(x) = f-1(x) is

18. The period of sin² θ is

19. Which of the following functions from Z into Z are bijective?

20. The binary operation * defined on N by a * b = a + b + ab for all a, b ∈ N is