Central angle intersection points and of the legs of the angle with the circle form a diameter, then is a straight angle. (In radians, .) Let be the minor arc of the circle between points and , and let be the radius of the circle. If the central angle is subtended by , then If the central angle is not subtended by the minor arc , then is a reflex angle and If a tangent at and a tangent at intersect at the exterior point , then denoting the center as , the angles (convex) and are supplementary (sum to 180°). A
Postmodern mathematics discussions of the philosophy of mathematics and mathematics education and has extensive articles on postmodern mathematics. He introduced the idea of 'fuzzy logic'. This idea rejects the Aristotelian Law of Truth and fallibility of an object (the notion that an object is either true or false). He instead proposed the existence of 'degrees of truth', the idea that an object is characterised into various degrees of truth. Thomas Kuhn (1922-1996) introduced the idea of paradigm shifts in sciences. he asserted that the paradigms and theories in sciences are not fixed but are instead on a continuum and hence are subject