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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

1 of 1

Application +4 | -1

Let

T_n

be the number of all possible triangles formed by joining vertices of an

n

-sided regular polygon. If

T_{n+1}-T_n=10

, the value of

n

is

View answer and explanation

Correct option: A

5

Option A (5) is correct because the equation

{T_{n + 1}} - {T_n} = 10

simplifies to

{^n}{C_2} = 10

, which is satisfied when n = 5.

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