in an a p 19th term is 52 and 38th term is 128 find the sum of first 56 terms
Answers
Answered by
0
Answer:
5040
Step-by-step explanation:
19th term=a+18d=52
30th term=a+37d=128
(2)−(1)⇒19d=76
d=4
a=-20
S56=2n [2a+(n−1)d]
20×180=5040
Similar questions