Question

find the sum of Frist (n) terms and sum of five terms 1 + 2^3 + 4 ^ 9 ------
​

Answer 1

Answer:

a=1

d=7

n=5

sum=5/2*(2*1+(5-1)7)

=75

sum of 5 terms will be 75

Answer 2

D dazzle yevedeya?????