Explicit formulas for geometric sequences

Problem

Mohamed and Li Jing were asked to find an explicit formula for the sequence minus, 5, space, comma, minus, 25, space, comma, minus, 125, space, comma, minus, 625, comma, point, point, point.
Mohamed said the formula is g, left parenthesis, n, right parenthesis, equals, minus, 5, dot, 5, start superscript, n, end superscript, and
Li Jing said the formula is g, left parenthesis, n, right parenthesis, equals, minus, 5, dot, 5, start superscript, n, minus, 1, end superscript.
Which one of them is right?
Choose 1 answer:
Choose 1 answer:
Do 4 problems