[解析]由归纳推理,可得原式=https://bgk-photo.cdn.bcebos.com/2934349b033b5bb56e648a9e26d3d539b600bc1b.jpg[3n 1-(-4)n 1](n∈N*)
[解析]由归纳推理,可得原式=https://bgk-photo.cdn.bcebos.com/2934349b033b5bb56e648a9e26d3d539b600bc1b.jpg[3n 1-(-4)n 1](n∈N*)
发布时间：2025-07-12 06:39:27
[3n 1-(-4)n 1]B组
