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JEE MATHEMATICS MCQ: COMBINATIONS

1 Easy

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Application +4 | -1

{\;^n}{C_r} + 2{\;^n}{C_{r - 1}} + {\;^n}{C_{r - 2}}

is equal to

View answer and explanation

Correct option: D

None of these

Option D (None of these) is correct because the simplified expression is

{\;^{n + 2}}{C_r}

, which is not among the given options.

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n