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Let * be a binary operation defined on Q. Find which of the following binary operations are associative a * b = abab4 for a, b ∈ Q. - Mathematics

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प्रश्न

Let * be a binary operation defined on Q. Find which of the following binary operations are associative

a * b = `"ab"/4` for a, b ∈ Q.

योग
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उत्तर

* is associative since Q is associative with respect to multiplication.

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अध्याय 1: Relations And Functions - Solved Examples [पृष्ठ ८]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 1 Relations And Functions
Solved Examples | Q 16. (ii) | पृष्ठ ८

संबंधित प्रश्न

Let A = Q ✕ Q, where Q is the set of all rational numbers, and * be a binary operation defined on A by (a, b) * (c, d) =  (ac, b + ad), for all (a, b) (c, d) ∈ A.
Find
(i) the identity element in A
(ii) the invertible element of A.

(iii)and hence write the inverse of elements (5, 3) and (1/2,4)


Determine whether or not of the definition of ∗ given below gives a binary operation. In the event that ∗ is not a binary operation, give justification for this.

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Determine whether or not of the definition of given below gives a binary operation. In the event that * is not a binary operation, give justification for this.

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Determine whether or not each of the definition of given below gives a binary operation. In the event that * is not a binary operation, give justification for this.

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Determine whether or not each of the definition of given below gives a binary operation. In the event that * is not a binary operation, give justification for this.

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For each binary operation * defined below, determine whether * is commutative or associative.

On Q, define ab + 1


Let A = × and * be the binary operation on A defined by  (ab) * (cd) = (cd)

Show that * is commutative and associative. Find the identity element for * on A, if any.


State whether the following statements are true or false. Justify.

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Let A = Q x Q and let * be a binary operation on A defined by (a, b) * (c, d) = (ac, b + ad) for (a, b), (c, d) ∈ A. Determine, whether * is commutative and associative. Then, with respect to * on A

1) Find the identity element in A

2) Find the invertible elements of A.


Determine whether or not the definition of * given below gives a binary operation. In the event that * is not a binary operation give justification of this.
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Here, Z+ denotes the set of all non-negative integers.


Determine whether or not the definition of *given below gives a binary operation. In the event that * is not a binary operation give justification of this.

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Here, Z+ denotes the set of all non-negative integers.


Determine whether or not the definition of * given below gives a binary operation. In the event that * is not a binary operation give justification of this.

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Let S be the set of all rational numbers of the form \[\frac{m}{n}\] , where m ∈ Z and n = 1, 2, 3. Prove that * on S defined by a * b = ab is not a binary operation.


Let * be a binary operation on N given by a * b = LCM (a, b) for all a, b ∈ N. Find 5 * 7.


Check the commutativity and associativity of the following binary operation '*'. on Z defined by a * b = a + b + ab for all ab ∈ Z ?


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Let S be the set of all rational numbers except 1 and * be defined on S by a * b = a + b \[-\] ab, for all a, b \[\in\] S:

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Choose the correct alternative:

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Let * be the binary operation defined on Q. Find which of the following binary operations are commutative

a * b = a – b ∀ a, b ∈ Q


If * is a binary operation on the set of integers I defined by a * b = 3a + 4b - 2, then find the value of 4 * 5.


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