Call this number n. It is x sub n equals a times r to the n - 1 power. Steps in Finding the General Formula of Arithmetic and Geometric Sequences.
S aₙ a₁ a₂ a₃.
Some of these problems will give you a sequence and then ask you about the terms or ratio of the sequence. Steps in Finding the General Formula of Arithmetic and Geometric Sequences. Repeat the process using an a2 a n a 2 to find a3 a 3 and then a3 a 3 to find a4 a 4 until all four terms have been identified. A geometric sequence is generated by two fixed quantities a and r none of them zero in the sense that every term is obtain by multiplying its previous term by r starting with a as its first term.