Edexcel IGCSE Maths 复习笔记 2.3.2 Expanding Two Brackets - Harder
Edexcel IGCSE Maths 复习笔记 2.3.2 Expanding Two Brackets - Harder Hidden FOIL (aka spot the hidden brackets) Always write (a + b)2 as (a + b)(a + b) Beware of minus signs Remember the basic rules:...