Consider the first four terms of an arithmetic sequence below. determine the recursive and explicit formulas that describe this sentence.

7, 13, 19 and 25 have a common difference:  6.  
6 added to 7 gives us 13; 6 added to 13 gives us 19, and so on.

Explicit formula:  a(n) = 7 + 6(n-1), where 7 is the first term and n is the counter (1, 2, 3, ...).

The first term is 7 (given).  This corresponds to n=1.

The second term is a(2) = 7 + 6(2-1), or 7 + 6, or 13.  This corresponds to n = 2.

and so on.

(2 - 3i)(4+2i)

(2 x 4)(2 x 2i) (-3i x 4) (-3i x 2i)

8 x 4i x -12i -6i^2

6i^2 - 12i x 32

Step-by-step explanation: