Question

Solve the above question

Answer 1

Answer:

The numbers are 1, 4 and 7.

Step-by-step explanation:

Let 3 numbers in A.P. be (a−d),a,(a+d)

⟹ Sum of 3 numbers =12

a−d+a+a+d=12

3a=12

a=4

⟹ sum of their cubes =408

(a−d)3 +a3 +(a+d)3 =408

a3 −d3 −3a2d+3a2d +a3 +a3 +d3 +3a2d+3ad2=408

3a3 +6ad2 =408

a3 +2ad2 =136

(4)3 +2(4)d2 =136

8d2 =136−64

8d2 =72

d2 =9

d=±3

If d=3, series ⟹4−3,4,4+3

⟹1,4,7

If d=−3, series ⟹4−(),4,4−3

⟹7,4,1

∴3 numbers are 1,4 and 7.

HOPE IT HELPS YOU

Answer 2

Step-by-step explanation:

this is your ans

hope it understand to u