Arithmetic and Geometric Sequences

Arithmetic or Geometric?

100

-4, 2, -1, 1/2

This is a Geometric sequence 

Common ratio: -1/2

200

2 1/2 , 3, 3 1/2, 4, 4 1/2...

What is Arithmetic?

300

2, 4, 6, 8...

What is Arithmetic?

400

-2, -4, -8, -16...

What is Geometric?

500

The sequence -5, -10, -15, -20

What is what is arithmetic?

find d or r

100

The Common Difference of -20, -23, -26, -29...

What is -3?

200

The Common Ratio of the Sequence 2, 4, 8, 16, 32...

What is 2 ?

300

The Common Difference of 18, 22, 26, 30...

What is 4?

400

The Common Ratio of the Sequence 3, 9, 27, 81...

What is 3?

500

The Common Ratio of the Sequence 1000, 200, 40, 8...

What is 1/5 or 0.2?

Find the missing term

100

Find the next 3 terms of the sequence: 

-12, -5, 2, ...

9, 16, 23

200

Find the 8th term of the sequence using the explicit formula a = 200(.5)^n-1 

1.5625

300

Find the 12th term of the sequence: 5, 16, 27, ...

126

400

Find the first three terms of the geometric sequence given the explicit formula: 

an = 2(3)^n-1

2, 6, 18

500

Find the 4th, 5th, and 6th term of the arithmetic sequence given the following explicit formula: 

a_n = 6n - 15 

9, 15, 21

Writing Equations (Geometric)

100

Write an equation for the nth term of the geometric sequences.

3, 15, 75, 375, 1875, ... 

a_n = 3*5^n-1

200

Write an equation for the nth term of the geometric sequences. 

324, 108, 36, 12, 4, ...

a_n) = 324 * (1/3

300

Write an equation for the nth term of the geometric sequences. 

1, -2, 4, -8, 16, ....

a_n=1 * (-2)^n-1

400

Write an equation for the nth term of the geometric sequences. Then find the 8th term

3, 6, 12, 24, ...

a_n= 3*(2)^n-1

a₈= 384

500

Write an equation for the nth term of the geometric sequences. Then find the 10th term

128, 64, 32, 16, 8, ...

a_n= 128(1/2)^n-1

a₁₀= 0.25

Writing Equations (Arithmetic)

100

Write an equation for the nth term of the arithmetic sequences. 

1, 4, 7, 10, 13, ...

a_n = 1 + (n - 1)3

200

Write an equation for the nth term of the arithmetic sequences. 

3, 8, 13, 18, 23, ...

a_n = 3 + (n - 1)5

300

Write an equation for the nth term of the arithmetic sequences. 

-8, -2, 4, 10, 16, ...

a_n = -8 + (n - 1)6

400

Write an equation for the nth term of the arithmetic sequences. Then find the 7th term.

-6, 1, 8, 15, 22, ...

a_n = -6 + (n - 1)7

a₇ = 36

500

Write an equation for the nth term of the arithmetic sequences. Find the 10th term

11, 4, -3, -10, -17, -24, ...

a_n = 11 + (n - 1)(-7)

a₁₀ = -52