Question

If the co-efficients of rth, (r+1) th and (r+2) th terms in the binomial expansion of (1+y)^m are in A.P. then m and r satisfy the equation

(a) m² - m (4r+1) + 4r² - 2 = 0 

(b) m² - (4r-1)m + 4r² + 2 = 0

(c) m² - (4r-1)m + 4r² - 2= 0 

(d) m² - (4r+1)m + 4r² + 2 = 0

Answer 1

Correct option: (a) m² - m (4r+1) + 4r² - 2 = 0

Explanation: