Question

Find three the numbers in GP such that their sum is 42 and sum of their square s is
1728​

Answer 1

Answer:

Step-by-step explanation:

Let the three number be a-d,a+d

Their sum is 42

a-d + a + a+d = 42

3a = 42

a = 14

The sum of their square is 1728

(a-d)2+(a)2+(a+d) = 1728

a2-2ad+d2+a2+a2+2ad+d2 = 1728

3(14)2+2d2 = 1728 (put a= 14)

3(196)+2d2 = 1728

588 + 2d2 = 1728

2d2 = 1140

d2 = 1140/2

d2 = 570

d = 23.87