Answer:
S8 is 64
Step-by-step explanation:
[tex]{ \boxed{ \bf{S_{n} = \frac{n}{2} [2a + (n - 1)d]}}}[/tex]
n is number of terms; n = 8
a is the first term; a = 1
d is the common difference: d = 3-1; d = 2
[tex]{ \sf{S_{8} = \frac{8}{2}[(2 \times 1) + (8 - 1) \times 2 ]}} \\ \\ { \sf{{S_{8}} = 4(2 + 14)}} \\ { \sf{S_{8}}} = 4 \times 16 \\ { \sf{S_{8}}} = 64[/tex]
