Review Sequences and Series

What kind of sequence is it?
 $3,\ 3^2,\ 3^3,\ 3^4,\ .\ .\ .$ 

• Cube number sequence

• Multiple of three sequence

• Arithmetic Sequence

• Geometric Sequence

• Indices Sequence

Find the next term of this sequence:

10, 8, 5, 1, . . .

• -6

• -5

• -4

• -3

Find the  $U_{n\ }$ formula of the sequence:
 $3,\ 14,\ 25,\ 36,\ .\ .\ .$ 

•  $U_n=3-11\left(n-1\right)$  
  

•  $U_n=3\ +\ 14\left(n-1\right)$  
  

•  $U_n=3\ +\ 11\left(n-1\right)$  

•  $U_n=n\ +3\left(14-1\right)$  
  

Find the 23rd term of the sequence:
 $-7,\ -5,\ -3,\ .\ .\ .$ 

• 35

• 36

• 37

• 39

Choose all the correct statements from the following options below.

• S₁ (Series) is the same with U₁ (Sequence)

• S₇ - S₆ will result U₇

• we can't find the series (the sum) if the given numbers are in a sequence form.

• $S_n=3n^{2\ }-\ 4n$ is the series formula for a geometric sequence.

• Rectangular sequence and triangular sequence are two of many examples of Arithmetic Sequence with constant second difference.

Find the 11th term of the sequence:

 $10,\ 20,\ 40,\ .\ .\ .$  

• 10240

• 5120

• 20480

• 2560

Find the sum of the first 50 numbers in this sequence:

 $\frac{1}{2}+\ 1+\frac{3}{2}+2+\frac{5}{2}+\ 3+.\ .\ .$  

• 635.5

• 625

• 625.5

• 637.5

Find the sum of the first 15 numbers in this sequence:

 $\frac{1}{2}+\frac{1}{4}+\frac{1}{8}+\frac{1}{16}+\frac{1}{32}+.\ .\ .$  

•  $\left(\frac{1}{2}\right)^{-15}$  
  

•  $2^{-15}$  
  

•  $\left(\frac{1}{2}\right)^{14}$  
  

•  $2^{14}$  
  

Fill in the gaps in this arithmetic sequence: -12, ___, ___, ___, ___, ___, 12

(Use format: Number1, number2, number3, . . .)

An arithmetic series has a sum of 9. The first term is 13 and the difference is -3. How many terms in the series?

(Write only number)