Answer:

1.In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members. The number of elements is called the length of the sequence.

2.Solution: Sequence A is an arithmetic sequence since every pair of consecutive terms has a common difference of −2, that is, d = − 2 d=-2 d=−2. On the other hand, sequence B is not an arithmetic sequence. There's no common difference among the pairs of consecutive terms in the sequence.

3.A geometric sequence is a sequence of numbers in which the ratio between consecutive terms is constant. where r is the common ratio between successive terms. Example 1: {2,6,18,54,162,486,1458,...}

Step-by-step explanation:

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