If sn denotes ,the sum of the first n term of arthmetic progression then prove that s12=3(s8-s4)

If sn denotes ,the sum of the first n term of arthmetic progression th

1.	If sn denotes ,the sum of the first n term of arthmetic progression then prove that s12=3(s8-s4)
Answer» S12=3(s8)