Question

Write the sum using summation notation, assuming the suggested pattern continues.

-10 - 2 + 6 + 14 + ... + 110

Answer 1

a=-10
d=-2-(-10)=-2+10=8
\[t _{n}=a+(n-1)d\]
110=-10+(n-1)*8
110+10=(n-1)*8
120/8=n-1
15+1=n
or~n=16
\[t _{n}=-10+(n-1)8=-10+8n-8=-18+8n=\sum_{n=1}^{16}\left( -18+8n \right)\]

Answer 2

last one is Sum but not tn

Answer 3

\[S=\sum_{n=1}^{16}\left( -18+8n \right)\]