### Home > CCA2 > Chapter 4 > Lesson 4.1.3 > Problem4-42

4-42.

This problem is a checkpoint for writing equations for arithmetic and geometric sequences. It will be referred to as Checkpoint 4A. Homework Help ✎

1. Write an explicit and recursive rule for $t(n) = 1, 4, 7, 10, ...$

2. Write an explicit and recursive rule for $t ( n ) = 3 , \frac { 3 } { 2 } , \frac { 3 } { 4 } , \frac { 3 } { 8 } , \dots$

In parts (c) and (d), write an explicit rule for the sequence given in the $n→t(n)$ tables.

1. An arithmetic sequence

 $n$ $t(n)$ $0$ $1$ $17$ $2$ $3$ $3$ $4$
1. A geometric sequence

 $n$ $t(n)$ $0$ $1$ $2$ $7.2$ $3$ $8.64$ $4$
1. If an arithmetic sequence has $t(7) = 1056$ and $t(12) = 116$, what is $t(4)$?