100% Proof! The Why of Maths: Visual and Algebraic Explanations of Formulas Needed for GCSE and a Level Mathematics

This book is a collection of over a hundred visual and algebraic explanations and proofs of maths formulas and concepts, all needed for GCSE and A level. Set out as very understandable individual pages per proof, with clear diagrams and simple algebra, all these formulas are found within one handy volume. This book is a good revision addition, key to understanding and memory aid. Black and white. Included are: Areas of rectangle, circle, triangle, parallelogram, trapezium, surface area and volume cone and sphere, ratio sides of triangle, Pythagoras, sine relationship, sine formula, sine area triangle, cosine rule, quadratic formula to find root, root relationships, circle theorems, trig identities, double angle, sums of sines, cosines, difference of two squares, completing the square, sum of geometric and arithmetic sequences, formula for circle…among others Often the ‘why of maths’ gets overlooked for the ‘how’ of using it, but these simple visual pages act as a key to understanding, and once understood, the maths becomes easier, it makes more sense, and the formulas are more likely to be remembered. The skills developed by using these pages are also fundamental to problem solving, finding an unknown, building on what you know to be true, experimenting, using logic. Such skills are essential for exam questions; problem solving is an important feature in current maths courses, as well as being a useful life skill.