Question

1.1

Answer 1

Answer:

The nth term of the arithmetic sequence is;

90 - 3n

Step-by-step explanation:

Here, we want to find an expression for the nth term of the sequence

Mathematically, let us determine the type of sequence

As we can see;

84 - 87 = 81-84 = -3

The difference between the terms is a constant; this means that the sequence is arithmetic

The nth term of an arithmetic sequence can be represented by;

Tn = a + (n-1)d

in this case, a is the first term of the sequence = 87

d is the common difference of the sequence = -3

The nth term is thus;

Tn = 87 + (n-1)-3

Tn = 87 - 3n + 3

Tn = 87 + 3 - 3n

Tn = 90 - 3n