Carr’s synopsis reveals much about cyclic quadrilaterals and the cosine rule. This Victorian text book is packed with sparse facts. Genius Ramanujan worked through these proving each one to himself. Modern students would extend their skills by doing the same. I have added some connections and associations to this sequence of facts to get you started. Should be within reach of year 11 pupils.
Properties of conic section have been known since classical times. This isosceles triangle in a parabola could still appear in school exams (FP1, STEP) in UK.
Carr’s Synopsis – 19th century text for self taught geniuses – marks out this A-star topic for I/GCSE maths hopefuls.