Different goals, shared foundations
All three reward the same basics: a fast, crawlable site, pages that genuinely answer questions, clear facts about who you are, and a reputation other sites confirm. Google states that the usual SEO best practices apply to its AI features, and there are no special tricks required to appear in them.
Where they differ is emphasis. SEO cares about rankings and clicks. AEO cares about the format of answers. GEO cares about how your brand is described and whether it gets recommended, which depends heavily on mentions and reviews elsewhere.
Which should a small business focus on?
Do not treat them as three projects. Build one content programme: answer the questions your buyers ask, in a quotable format, on a technically sound site, and earn mentions on trusted sites. That one programme serves classic search and AI search together.
ForceMX's Marketing department runs SEO and AEO as a single programme and tracks both search rankings and AI mentions.