Question

Generalize the pattern by finding a formula to calculate the nth term.

1, 5, 9, 13, 17, 21,...



A)
4n



B)
n + 4


C)
4n - 3


D)
4n + 4

Answer 1

It's an arithmetic sequence. The first term is 1 and the common difference is 4.


`a_1=1 \\ d=4 \\ \\ a_n=a_1+d(n-1) \\ a_n=1+4(n-1) \\ a_n=1+4n-4 \\ \boxed{a_n=4n-3} \\ \hbox{answer C}`