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JEE MATHEMATICS MCQ: COMBINATIONS

1 Easy

1 of 1

Application +4 | -1

Find

{ }^n C_{21}

, if

{ }^n C_{10}={ }^n C_{11}

.

View answer and explanation

Correct option: A

1

Option A (1) is correct because given

{ }^n C_{10}={ }^n C_{11}

, we find

n=21

, and

{ }^{21} C_{21}=1

.

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