LLLLL9. If 9th term of an A.P. is zero, prove that its 29th term is do

1.	LLLLL9. If 9th term of an A.P. is zero, prove that its 29th term is double the 19th to10th term of an A.P. is equal to 15 times the 15th term, show the
Answer» Let first term of an AP is a and Common difference d 9th terma + 8d = 0a = - 8d...........(1) 29th terma29 = a + 28d = - 8d + 28d = 20d 19th terma19 = a + 18d = - 8d + 18d = 10d Therefore, a29 = 2 a19

LLLLL9. If 9th term of an A.P. is zero, prove that its 29th term is double the 19th to10th term of an A.P. is equal to 15 times the 15th term, show the

Answer»

Let first term of an AP is a and Common difference d

9th terma + 8d = 0a = - 8d...........(1)

29th terma29 = a + 28d = - 8d + 28d = 20d

19th terma19 = a + 18d = - 8d + 18d = 10d

Therefore, a29 = 2 a19