Question

Find the sum of first 8 odd natural numbers

Answer 1

odd natural no. is 1,3,5,..... so on
according to a. p.
1,3,5,....
a = 1 , d = 2 , n = 8
sum of n natural no. of an A. P. is n/2[2a + (n - 1) d]
sum of first 8 odd natural no. 's is 8/2[2a + (n-1)d]
4[2a +(n-1)d]
put the value of a and d
4[2(1)+(8-1)2]
4[2(1 )+ (7*2)]
4[2 + 14]
4[16]
64