Let A = {1, 2, 3, \ldots , 10} and B = { m n : m, n \in A, m < n and gcd(m, n) = 1}. Then n(B) is equal to :
If the range of $f(\theta)=\dfrac{\sin^4\theta+3\cos^2\theta}{\sin^4\theta+\cos^2\theta}$, $\theta\in\mathbb{R}$, is $[\alpha,\beta]$, then the sum of the infinite G.P., whose first term is 64 and the common ratio is $\dfrac{\alpha}{\beta}$, is equal to ________.
Let $S = \{p_1, p_2, \ldots, p_{10}\}$ be the set of first ten prime numbers. Let $A = S \cup P$, where $P$ is the set of all possible products of distinct elements of $S$. Then the number of all ordered pairs $(x, y)$, $x \in S$, $y \in A$, such that $x$ divides $y$, is ___
Let X = R \times R. Define a relation R on X as : (a1 , b1 ) R (a2 , b2 ) \Leftrightarrow b1 = b2 Statement I : R is an equivalence relation. Statement II : For some (a, b) \in X, the set S = {(x, y) \in X : (x, y)R(a, b)} represents a line parallel to y = x. In the light of the above statements, choose the correct answer from the options given below :
Let S = {p , p \ldots . , p 1 2 10 } be the set of first ten prime numbers. Let A = S \cup P , where P is the set of all possible products of distinct elements of S . Then the number of all ordered pairs ( x, y ), x \in S , y \in A, such that x divides y , is ______.
Let R = {(1, 2), (2, 3), (3, 3)} be a relation defined on the set {1, 2, 3, 4}. Then the minimum number of elements, needed to be added in R so that R becomes an equivalence relation, is: