Maths-

General

Easy

Question

# If = mC_{2}, then C_{2} is equal to -

Hint:

### We will expand the value of α=mC2 using nCr=n!r!(n−r)!. Similarly, simplify αC2 and then substitute the value of α in the expression of αC2. Then, use the property of factorial and simplify the expression to get the required answer.

## The correct answer is:

Students must know how to open expressions like nCr.

Also, the value of n! is n.(n−1).(n−2).....3.2.1.

Combination is used to select r objects from n objects when the arrangement of the objects does not matter.

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