Irrational number number to ratios of continuous magnitude. In his commentary on Book 10 of the "Elements", the Persian mathematician Al-Mahani (d. 874/884) examined and classified quadratic irrationals and cubic irrationals. He provided definitions for rational and irrational magnitudes, which he treated as irrational numbers. He dealt with them freely but explains them in geometric terms as follows: In contrast to Euclid's concept of magnitudes as lines, Al-Mahani considered integers and fractions as rational magnitudes, and square roots and cube roots as irrational magnitudes. He also introduced an arithmetical approach to the concept of irrationality, as he attributes the following to irrational
Fear Is the Key (film) Fear Is the Key (film) Fear Is the Key is a 1972 film directed by Michael Tuchner and based on the 1961 novel of the same name by Alistair MacLean. The protagonist, Talbot, was played by Barry Newman, and the millionaire's daughter Sarah Ruthven by Suzy Kendall. The film features a soundtrack by Roy Budd plus an early film appearance by Ben Kingsley. John Talbot is talking on radio to a girl and another man who are flying a plane. He hears them being machine gunned to death by another plane. Some time later, Talbot appears in a small town