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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

1 of 1

Application +4 | -1

Let

A

be a set of

n(\geq 3)

distinct elements. The number of triplets

(x, y, z)

of the set

A

in which atleast two coordinates are equal to

View answer and explanation

Correct option: B

n^3-{ }^n P_3

Option B (

n^3-{ }^n P_3

) is correct because it calculates the total number of triplets minus the number of triplets with all distinct elements.

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