Group Theory


Q11.

For the composition table of a cyclic group shown below Which one of the following choices is correct?
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Q12.

Let P, Q and R be sets, let \triangle denote the symmetric difference operator defined as P\triangle Q=(P \cup Q) - (P \cap Q). Using Venn diagrams, determine which of the following is/are TRUE? I. P \Delta(Q \cap R)=(P \Delta Q) \cap(P \Delta R) II. P \cap(Q \cap R)=(P \cap Q) \Delta(P \Delta R)
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Q13.

The set {1, 2, 3, 5, 7, 8, 9} under multiplication modulo 10 is not a group. Given below are four plausible reasons. Which one of them is false?
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Q14.

How many different non-isomorphic Abelian groups of order 4 are there?
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Q15.

Consider the set H of all 3 x 3 matrices of the type \begin{bmatrix} a & f & e\\ 0 & b & d\\ 0&0 & c \end{bmatrix} where a,b,c,d,e and f are real numbers and abc\neq0. Under the matrix multiplication operation, the set H is:
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Q16.

Let \left(Z, *\right) be an algebraic structure where Z is the set of integers and the operation * is defined by n*m = \max(n,m). Which of the following statements is true for \left(Z, *\right)?
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Q17.

Some group (G, o) is known to be abelian. Then, which one of the following is true for G?
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Q18.

Two girls have picked 10 roses, 15 sunflowers and 15 daffodils. What is the number of ways they can divide the flowers among themselves?
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Q19.

Consider the set \Sigma ^{*} of all strings over the alphabet \Sigma ={0,1}. \Sigma ^{*} with the concatenation operator for strings
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Q20.

Which of the following is true?
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