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In the set N of natural numbers, define the binary operation * by m * n = g.c.d (m, n), m, n ∈ N. Is the operation * commutative and associative? - Mathematics

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प्रश्न

In the set N of natural numbers, define the binary operation * by m * n = g.c.d (m, n), m, n ∈ N. Is the operation * commutative and associative?

योग

उत्तर

The operation is clearly commutative since

m * n = g.c.d (m, n) = g.c.d (n, m) = n * m ∀ m, n ∈ N.

It is also associative because for l, m, n ∈ N, we have

l * (m * n) = g. c. d (l, g.c.d (m, n))

= g.c.d. (g. c. d (l, m), n)

= (l * m) * n.

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अध्याय 1: Relations And Functions - Solved Examples [पृष्ठ ४]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 1 Relations And Functions
Solved Examples | Q 11 | पृष्ठ ४

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