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Let R0 Denote the Set of All Non-zero Real Numbers and Let a = R0 × R0. If '*' is a Binary Operation on a Defined by (A, B) * (C, D) = (Ac, Bd) for All (A, B), (C, D) ∈ Afind the - Mathematics

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प्रश्न

Let R0 denote the set of all non-zero real numbers and let A = R0 × R0. If '*' is a binary operation on A defined by

(a, b) * (c, d) = (ac, bd) for all (a, b), (c, d) ∈ A

Find the identity element in A ?

योग
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उत्तर

\[\text{Let} \left( x, y \right) \text{be the identity element in A} \forall \left( x, y \right) \in \text{ A . Then }, \] 
\[\left( a, b \right) * \left( x, y \right) = \left( a, b \right) = \left( x, y \right) * \left( a, b \right) \] 
\[ \Rightarrow \left( a, b \right) * \left( x, y \right) = \left( a, b \right) \text{ and } \left( x, y \right) * \left( a, b \right) = \left( a, b \right)\] 
\[ \Rightarrow \left( ax, by \right) = \left( a, b \right) \text{ and } \left( xa, yb \right) = \left( a, b \right)\] 
\[ \Rightarrow x = 1 \text{ and } y = 1 \] 
\[\text{Thus }, \left( 1, 1 \right) \text{is the identity element of A } . \] 

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अध्याय 3: Binary Operations - Exercise 3.4 [पृष्ठ २५]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 3 Binary Operations
Exercise 3.4 | Q 7.2 | पृष्ठ २५

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