Question

The coefficient of 3 consecutive terms in (1+a)ⁿ is 1:7:42

Answer 1

Answer:

Example 9 The coefficients of three consecutive terms in the expansion of (1 + a)n are in the ratio 1: 7 : 42. ... Let the three consecutive terms be (r – 1)th, rth and (r + 1)th terms.