The first four terms of a sequence are \text{3, -6, 12, -24}. write an explicit formula for this sequence, where n is any term number and a\left(n\right) is the nth term

see explanation

Step-by-step explanation:

The terms form a geometric sequence with n th term

= a

where a is the first term and r the common ratio

r = = = ......

r = = = - 2 and a = 3, hence

= 3 ← explicit formula