JEE Mains · Maths · STD 12 - 1. relation and function
Let \(A=\{2,3,6,7\}\) and \(B=\{4,5,6,8\}\). Let \(R\) be a relation defined on A \(\times\) B by \(\left(a_1, b_1\right) R\left(a_2, b_2\right)\) is and only if \(a_1+a_2=b_1+b_2\). Then the number of elements in \(\mathrm{R}\) is ...........
- A \(34\)
- B \(25\)
- C \(31\)
- D \(20\)
Answer & Solution
Correct Answer
(B) \(25\)
Step-by-step Solution
Detailed explanation
\( A=\{2,3,6,7\} \) \( B=\{2,5,6,8\} \) \( \left(a_1, b_1\right) R\left(a_2, b_2\right) \) \( a_1+a_2=b_1+b_2\) \(1\). \((2,4) \mathrm{R}(6,4) \quad\) 2. \((2,4) \mathrm{R}(7,5)\) \(3\). \((2,5) \mathrm{R}(7,4) \quad\) 4. \((3,4) \mathrm{R}(6,5)\) \(5\).…
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