Answer :
Step 1: Write out the formula for the nth term of an arithmetic sequence
[tex]U_n=a+(n-1)d[/tex]Step 2: Find a and d and substitute them into the formula
[tex]\begin{gathered} a=8 \\ d=U_2-U_1 \\ d=26-8=18 \\ Un=8+(n-1)18 \end{gathered}[/tex]Step 3: find the 77th term
[tex]\begin{gathered} U_{77}=8+(77-1)18 \\ =8+(76)18 \\ =8+1368 \\ U_{77}=1376 \end{gathered}[/tex]Hence, the 77th term is 1376