Let S= _ r=1 ^ 10 ((r+3)!-(r+1)!-8 ((r+1)!-r! ) ) be an A.P. If _ r=1 ^ 10 ((r+3)!-(r+1)! )-8 _ r=1 ^ 10...

Question

Let S= _ r=1 ^ 10 ((r+3)!-(r+1)!-8 ((r+1)!-r! ) ) be an A.P. If _ r=1 ^ 10 ((r+3)!-(r+1)! )-8 _ r=1 ^ 10 ((r+1)!-r! ), the product =12!+13!-2!-3!-8 (11!-1! ) is minimum and the sum of its first n terms is zero, then n!-4a_ n(n+2) is equal to

Accepted Answer

(A)

JEE Main Mathematics question

Solution

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