Question

If 9th term of anA.P.is zero,prove that the 29thterm is double the19th term .

Answer 1

Answer:

0 = a+8d

a29= a+28d

a29=a+8d+20d

a29=20 eq -1

a19=a+18d

a19= a+8d+10d

a19=10d eq- 2

from 1 & 2

we know that a29= 2×a19