Question

In Exercises 1–6, write the first five terms of the sequence whose th term is given.

1. A_n = 3^n
2. A_n = (-2/5)^n
3. A_n = sin npi/2
4. A_n = 3n/n + 4
5. A_n = (-1)^n+1(2/n)
6. A_n = 2 + 2/n - 1/n^2

Answer 1

Explanation:

1. Un = 3^ n

U1 = 3, U2 = 9, U3 = 27, U4 = 81, U5 = 243

2. Un = (-2/5)^n

U1 = -2/5, U2 = 4/25, U3 = 8/125, U4 = 16/625, U5 = 32/3125

3. Un = sin npi/2

U1 = 1, U2 = 0, U3 = -1, U4 = 0, U5 = -1

4. Un = 3n/n+4

U1 = 3/5, U2 = 1, U3 = 9/7, U4 = 3/2, U5 = 5/3

5. Un = (-1)^n+1(2/n)

U1 = 1, U2 = 2, U3 = -1/3, U4 = 3/2, U5 = -3/5

6. Un = 2 + 2/n - 1/n^2

U1 = 3, U2 = 11/4, U3 = 23/9, U4 = 39/16, U5 = 59/25