GCSE Maths (video lessons, examples, solutions, worksheets, activities ... May 2013. The following table gives the formulae that you need to know for the Edexcel GCSE (9-1) Maths: Areas, Volumes, Circles, Compound Measures, Pythagoras, Trigonometric Formulae, Quadratic Equations. Show Formulas. These Revision Videos will give you a quick revision for some common GCSE exam style topics and questions.