Q. 51

# State whether the statements in True or False.

There are 12 points in a plane of which 5 points are collinear, then the number of lines obtained by joining these points in pairs is ^{12}C_{2} – ^{5}C_{2}.

Answer :

FALSE

Required number of lines are ^{12}C_{2} – ^{5}C_{2} + 1

the number of lines obtained by joining these points in pairs is ^{12}C_{2} – ^{5}C_{2}+1.

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Prove that the product of 2n consecutive negative integers is divisible by (2n)!

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