What is the nth term rule of the linear sequence below?
-4,-1,2,5,8,...

The nth term of the given sequence  tₙ = 3 n - 7

Step-by-step explanation:

Given sequence   - 4 , -1 , 2 , 5, 8 , .....

First term a = -4

The difference of two terms of a given sequence

d = -1 - (-4) = -1 +4 = 3

d = 2 - (-1) = 2 +1 = 3

d = 5 -2 = 3

d = 8 - 5 =3

The difference of two terms of a given sequence is equal

∴ The given sequence is in Arithmetic progression(AP)

     The nth term of given sequence

Final -

The nth term of the given sequence  tₙ = 3 n - 7

step-by-step explanation:

part a. the differences are decreasing, so we know the sequence is not arithmetic. the ratios are constant (=3/4), so we know the sequence is geometric.

part b. from part a, we know the common ratio is 3/4, so each term is 3/4 of the one before. the initial term is the number of gallons at h=1.

g[h] = (3/4)·g[h-1]

g[1] = 384 . . . . initial value required for a recursive definition

part c. the general formula for a geometric sequence is

a[n] = a[1]·r^(n-1)

we have a[1] = 384, r = 3/4, and the term number given by h. the formula that follows is

g[h] = 384·(3/4)^(h-1)

part d. filling in the value and doing the arithmetic, we have

g[12] = 384·(3/4)^11 ≈ 384·0.042235136 ≈ 16.2183 . . gallons

part e. each gallon is 4 quarts, so

16.2183 gal × 4 qt/gal = 64.8732 qt