Fear of needles Fear of needles Fear of needles, known in medical literature as needle phobia, is the extreme fear of medical procedures involving injections or hypodermic needles. It is occasionally referred to as "aichmophobia" or "belonephobia", although these terms may also refer to a more general fear of sharply pointed objects. It has also been referred to as "trypanophobia", although the origin and proper usage of that term is highly controversial. The condition was officially recognized in 1994 in the DSM-IV (Diagnostic and Statistical Manual, 4th edition) as a specific phobia of blood/injection/injury type. Phobic level responses to injections cause sufferers to
Irrational number During the 14th to 16th centuries, Madhava of Sangamagrama and the Kerala school of astronomy and mathematics discovered the infinite series for several irrational numbers such as "π" and certain irrational values of trigonometric functions. Jyeṣṭhadeva provided proofs for these infinite series in the "Yuktibhāṣā". In the Middle ages, the development of algebra by Muslim mathematicians allowed irrational numbers to be treated as "algebraic objects". Middle Eastern mathematicians also merged the concepts of "number" and "magnitude" into a more general idea of real numbers, criticized Euclid's idea of ratios, developed the theory of composite ratios, and extended the concept of