Question

The fourth term of an ap is zero prove that the 25th term of an ap is a three times its 11th term

Answer 1

Answer:

Step-by-step explanation:

a4=0

a + 3d=0

a=-3d     ---------- 1

a25=a+24d

      =-3d +24d

      =21d          -------------------- 2

3 x a11=3(a+10d)

          =3(-3a +10d)

          =3 x 7d

          =21d  ------------------------- 3

from 2&3

3x a11=a25