Question

A recursive rule for an arithmetic sequence is a1=-4 an=4+a (n-1)
What is the 4th term?

Answer 1

4th term is 8

Explanation:

`\left\{\begin{array}{ccc}a_1=-4\\a_n=4+a_(n-1)\end{array}\right\\\\a_2=4+a_1\to a_2=4+(-4)=4-4=0\\\\a_3=4+a_2\to a_3=4+0=4\\\\a_4=4+a_3\to a_4=4+4=8`