Introduction to sequences

1003085005

Level: 
A
A sequence \( \left( a_n \right)_{n=1}^{\infty} \) is defined by the recursive formula \( a_1=1;\ a_{n+1}=\frac1{1+a_n}\text{, }n\in\mathbb{N} \). What are its first five terms?
\( 1 \), \( \frac12 \), \( \frac23 \), \( \frac35 \), \( \frac58 \)
\( 1 \), \( \frac12 \), \( \frac23 \), \( \frac34 \), \( \frac58 \)
\( 1 \), \( 2 \), \( \frac32 \), \( \frac53 \), \( \frac85 \)
\( 1 \), \( \frac12 \), \( \frac32 \), \( \frac35 \), \( \frac85 \)

1003085006

Level: 
A
A sequence \( \left(a_n\right)_{n=1}^{\infty} \) is defined by the recursive formula \( a_1=1\text{, }a_2=2;\ a_{n+2} = \frac12\left(a_{n+1}+a_n\right)\text{, }n\in\mathbb{N} \). What are its first five terms?
\( 1 \), \( 2 \), \( \frac32 \), \( \frac74 \), \( \frac{13}8 \)
\( 1 \), \( 2 \), \( \frac32 \), \( \frac47 \), \( \frac8{13} \)
\( 1 \), \( 2 \), \( 3 \), \( 7 \), \( 13 \)
\( 1 \), \( 2 \), \( \frac23 \), \( \frac47 \), \( \frac{13}8 \)

1003107310

Level: 
A
We are given a sequence \( \left( a_n \right)^{\infty}_{n=1} \) defined recursively by: \( a_1=1,\ a_2=2\,;\ a_{n+2}=\frac12\left( a_{n+1}+a_n\right),\ n\in\mathbb{N} \). Find the sum of the first four terms of this sequence.
\( \frac{25}4 \)
\( \frac{63}8 \)
\( \frac{13}4 \)
\( \frac4{25} \)

1103084905

Level: 
A
Which sequence is defined by the given graph?
\( \left( a_n \right)^{5}_{n=1} = 2\text{, }\ 1\text{, }\ 3\text{, }\ 1\text{, }\ 2 \)
\( \left( a_n \right)^{10}_{n=1} = 1\text{, }\ 2\text{, }\ 2\text{, }\ 1\text{, }\ 3\text{, }\ 3\text{, }\ 4\text{, }\ 1\text{, }\ 5\text{, }\ 2 \)
\( \left( a_n \right)^{5}_{n=1} = 1\text{, }\ 2\text{, }\ 3\text{, }\ 4\text{, }\ 5 \)
\( \left( a_n \right)^{5}_{n=1} = 1\text{, }\ 1\text{, }\ 2\text{, }\ 2\text{, }\ 3 \)