JEE Main Questions
Find the coefficient of x5 in the expansioin of the product (1+2x)6(1−x)7˙
There are two bags each of which contains n balls. A man has to select an equal number of balls from both the bags. Prove that the number of ways in which a man can choose at least one ball from each bag is2nCn−1.
If a1,a2,a3,a4 be the coefficient of four consecutive terms in the expansion of (1+x)n, then prove that: a1+a2a1+a3+a4a3=a2+a32a2˙
Show that the middle term in the expansion of (1+x)2nis n!18.104.22.168n−1˙˙2nxn2nxn, where n is a positive integer.
Find the value of