Question

The sum of an A P is 5n2+n.
Find the nth term *​

Answer 1

Answer:

Sum of 1 term = 5*1/2 + 3(1)/2 = 8/2 = 4 . ... Second term = 13 - 4 = 9 . Common difference = 9 - 4 = 5 . 20 th term = a + ( 20 - 1 )d = a+19d = 4 + 19(5) = 99 .