Function


Q1.

Let f:A\rightarrow B be an onto (or surjective) function, where A and B are nonempty sets. Define an equivalence relation \sim on the set A as a_1\sim a_2 \text{ if } f(a_1)=f(a_2), where a_1, a_2 \in A . Let \varepsilon =\{[x]:x \in A\} be the set of all the equivalence classes under \sim . Define a new mapping F: \varepsilon \rightarrow B as F([x]) = f(x), for all the equivalence classes [x] in \varepsilonWhich of the following statements is/are TRUE?
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Q2.

Which one of the following is the closed form for the generating function of the sequence \{a_n \}_{n \geq 0} defined below?a_n= \left \{ \begin{matrix} n+1, &n \text{ is odd} \\ 1,& \text{otherwise} \end{matrix} \right.
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Q3.

Consider the following sets, where n\geq 2: S1: Set of all nxn matrices with entries from the set \{a, b, c\} S2: Set of all functions from the set\{0,1,2,...,n^2-1\} to the set \{0, 1, 2 \} Which of the following choice(s) is/are correct?[MSQ]
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Q4.

If the ordinary generating function of a sequence \{a_{n}\}_{n=0}^{\infty} \; is \; \frac{1+z}{(1-z)^{3}} then a_{3}-a_{0} is equal to ______.
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Q5.

Let A be a finite set having x elements and let B be a finite set having y elements. What is the number of distinct functions mapping B into A.
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Q6.

Let f: B \rightarrow C and g: A \rightarrow B be two functions and let h = f\cdotg. Given that h is an onto function which one of the following is TRUE?
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Q7.

Suppose X and Y are sets and |X| and |Y| are their respective cardinality. It is given that there are exactly 97 functions from X to Y. From this one can conclude that
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Q8.

Let : A\rightarrowB be injective (one-to-one) function. Define g:2^{A}\rightarrow 2^{B} as: g(C) = {f (x)| x \inC), for all subsets C of A. Defineg:2^{B}\rightarrow 2^{A} as : h(D) = {x | x \in A, f (x) \in D}, for all subsets D of B. Which of the following statements is always true?
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Q9.

Consider the set of all functions f:{0,1,...,2014}\rightarrow{0,1...,2014} such that f(f(i))=i, for 0\leqi\leq2014 . Consider the following statements. P. For each such function it must be the case that for every i, f(i) = i, Q. For each such function it must be the case that for some i,f(i) = i, R. Each such function must be onto. Which one of the following is CORRECT?
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Q10.

If f(x_{i}).f(x_{i+1}) \lt 0 then
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