Consider a rule `f(x)=2x-3` associating elements of `NN` (set of natural numbers) to elements of `NN`. Is it a function?

Let A be a set represented by the squares of natural numbers and x,y are any two elements of A then

prove that a function f = {(x,2x+1) : x in N} defined on the set of natural numbers NxxN is one - one function.

The number of elements of the power set of a set containing n elements is

Let L denotes the number of subjective functions f : A -> B , where set A contains 4 elementset B contains 3 elements. M denotes number of elements in the range of the function f(x) = sec^-1(sgmx) + cosec^-1(sgn x) where sg n x denotes signum function of x. And N denotes coefficient of t^5 in (1+t^2)^5(1+t^3)^8 . The value of (LM+N) is lambda , then the value of lambda/19 is

If the set A contains 5 elements, then the number of elements in the power set P(A) is equal to

Consider all 3 element subsets of the set {1, 2, 3, ………. 300} then:

Let f\ be a relation on the set NN of natural numbers defined by f={(n ,3n): n in NN} is f a function from NN\ to\ NN . If so, find the range of f .

Which of the following sets of real numbers is such that if x is an element of the set and y is an element of the set, then the sum of x and y is an element of the set ? I. The set of negative integers II. The set of rational numbers III. The set of irrational numbers

If the number of elements in the power set of set A is 128 then find the number of elements in the set A .

If the set A contains 5 elements and the set B also contains 5 elements, then find the number of bijective functions from A to B.