SOLUTION:
Case: Geometric sequence
Method:
Sequence: -1, -2, -4, -8, ...
1. Type: Geometric/ Exponential sequence
2. Since the common ratio is 2. The recursive function is:
[tex]\begin{gathered} a_n=a_{n-1}\cdot r \\ a_n=a_{n-1}\cdot2 \end{gathered}[/tex]
3. The value of a1 (first term)
[tex]a_1=-1[/tex]
