Q. 34.5( 23 Votes )

# Let * be a binary operation on N given by a*b = LCM(a,b) for all a,b∈N. Find 5*7.

Answer :

Given that * is an operation that is valid for the natural numbers ‘N’ and is defined by a*b = LCM(a,b).

We need to find the value of 5*7.

According to the Problem, Binary operation is assumed to be true for the values of a and b to be natural.

⇒ 5*7 = LCM(5,7)

We know that LCM of two prime numbers is the product of that given two prime numbers.

⇒ 5*7 = 5×7

⇒ 5*7 = 35

∴ The value of 5*7 is 35.

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