Answer:
1) arithmetic. 36, 43.
2) geometric. 1215, 3645.
3) neither.
4) geometric. 6875, 234375.
Step-by-step explanation:
First, let's remember the definition of both arithmetic and geometric sequence.
A geometric sequence is a sequence of numbers where each term is found by multiplying the previous term by a fixed value.
An arithmetic sequence is a sequence of numbers where each term is found by adding a fixed value to the previous term.
Now, let's examine the sequences given:
1, 8, 15, 22, 29,.. this is an arithmetic sequence (adding 7 to each term), the next two terms would be 36, 43.
5, 15, 45, 135, 405... this is a geometric sequence (multiplying by 3). The next two terms are: 1215, 3645
13, 14,21, 28, 35,.. this is neither a geometric or an arithmetic sequence (if it hadn't 13 as a first term then it would be an arithmetic sequence and the next two numbers would be 42, 49)
15, 75, 375, 1875, 9375,.. this is a geometric sequence (multiplying by 5). The next two terms are 46875, 234375.