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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 ∈ S: Prove that * is a Binary Operation on S ? - Mathematics

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प्रश्न

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:

Prove that * is a binary operation on S ?

योग

उत्तर

We have,

S = \[-\] {1} and * is defined on S as a * b = a + b \[-\]ab, for all a, b \[\in\] S

It is seen that for each a, b \[\in\] S, there is a unique element a + b \[-\] ab in S

This means that * carries each pair (a, b) to a unique element a * b = a + b \[-\] ab in S

So, * is a binary operation on S

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अध्याय 3: Binary Operations - Exercise 3.2 [पृष्ठ १३]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 3 Binary Operations
Exercise 3.2 | Q 14.1 | पृष्ठ १३

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