Question

What is the recursive rule for an=4n−1?

Answer 1

The correct answer is the first one a1=3;an=an−1+4 

Answer 2

Answer:

Option 1 is correct that is $a_1=3,a_n=a_{n-1}+4$

Step-by-step explanation:

We have given $a_n=4n-1$

We will put different values of n to get the recursive formula:

When n=1 in  $a_n=4n-1$ we get

$a_1=4(1)-1=3$

When n=2 in $a_n=4n-1$ we get

$a_2=4(2)-1=7$

When n=3 in $a_n=4n-1$ we get

$a_3=4(3)-1=11$

We can clearly see the difference between consecutive terms is 4

Hence, recursive formula will become

$a_1=3,a_n=a_{n-1}+4$

Therefore Option 1 is correct that is $a_1=3,a_n=a_{n-1}+4$