Question

the sum of 3 consecutive terms of an ap is 9 and the sum of their squares is 77 find the terms?

Answer 1

Here is your answer :-

Three consecutive numbers are a-d , a and a+d

ATQ ,

a-d +a+a+d = 9

3a = 9

a = 3 -----(1)

now ,

(a-d)² + a² + (a+d)² = 77

(3-d)² + 9 + (3+d)² = 77

9 + d² -6d +9 +9 +d² + 6d = 77

27 + 2d² = 77

2d² = 50

d² = 25

d = 5

so the terms are -2 , 3 and 8