Question

If `""^mC_3 + ""^mC_4 > ""^(m+1)C_3`, then least value of m is ______.

Options

• 6

• 7

• 5

• 4

Answer 1

If `""^mC_3 + ""^mC_4 > ""^(m+1)C_3`, then least value of m is 7.

Explanation:

`""^mC_3 + ""^mC_4 > ""^(m+1)C_3`

⇒ `(""^(m+1)C_4)/(""^(m+1)C_3) > 1`

⇒ `underline(|m + 1)/underline(|4|m - 3) . underline(|3|m - 2)/underline(|m + 1) > 1`

⇒ `(m - 2)/4 > 1`

⇒ m > 6

Least value of m is 7