Question

Which recursive formula can be used to reresent the sequence 2,6,10,14,18

1. a = 0
1
a = a + 4
n n-1


2. a = 2
1
a = a +4
n-1 n

3. a = 2
1
a = a -4
n n-1

4. a = 2
1
a = a +4
n n-1

Answer 1

`4.\\\left\{\begin{array}{ccc}a_1=2\\a_n=a_(n-1)+4\end{array}\right\\\\check\\\\a_2=a_1+4\to a_2=2+4=6\\\\a_3=a_2+4\to a_3=6+4=10\\\\a_4=a_3+4\to a_4=10+4=14\\\\a_5=a_4+4\to a_5=14+4=18`