Let S = {1,2,3,..., 20}, R1 = {(a, b): a divide b}, R2 = {(a, b): a is integral multiple of b} and a, b ∈ S. n(R1 - R2) = ?

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Let S = {1,2,3,..., 20}, R₁ = {(a, b): a divide b}, R₂ = {(a, b): a is integral multiple of b} and a, b ∈ S. n(R₁ - R₂) = ?

Updated On: Mar 16, 2026

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Solution and Explanation

The result is 46.

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Let S = {1,2,3,..., 20}, R1 = {(a, b): a divide b}, R2 = {(a, b): a is integral multiple of b} and a, b ∈ S. n(R1 - R2) = ?

Solution and Explanation

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Questions Asked in JEE Main exam

Let S = {1,2,3,..., 20}, R₁ = {(a, b): a divide b}, R₂ = {(a, b): a is integral multiple of b} and a, b ∈ S. n(R₁ - R₂) = ?