To answer this question, we can use the explicit formula of an arithmetic sequence:
[tex]a_n=a_1+(n-1)d[/tex]
• We have that the first term (a1) of the arithmetic sequence is 6 (a1 = 6).
,
• The common difference is 3 (d = 3).
Then, we have that the formula is:
[tex]a_n=6+(n-1)\cdot3=6+3(n-1)[/tex]
We can use this formula to find the 20th term of this arithmetic sequence as follows:
[tex]a_{20}=6+3\cdot(20-1)=6+3\cdot(19)=6+57=63\Rightarrow a_{20}=63[/tex]
In summary, the formula for the arithmetic sequence is:
[tex]a_n=6+3(n-1)[/tex]
And the 20th term is equal to 63.
