In mathematics
45 is an odd number and a Størmer number. 45 degrees is half of a right angle. It is also the smallest positive number that can be expressed as the difference of two nonzero squares in more than two ways: , or . [1]
| ||||
|---|---|---|---|---|
| Cardinal | forty-five | |||
| Ordinal | 45th (forty-fifth) | |||
| Factorization | 32 × 5 | |||
| Divisors | 1, 3, 5, 9, 15, 45 | |||
| Greek numeral | ΜΕ´ | |||
| Roman numeral | XLV, xlv | |||
| Binary | 1011012 | |||
| Ternary | 12003 | |||
| Senary | 1136 | |||
| Octal | 558 | |||
| Duodecimal | 3912 | |||
| Hexadecimal | 2D16 | |||
45 (forty-five) is the natural number following 44 and preceding 46.
45 is an odd number and a Størmer number. 45 degrees is half of a right angle. It is also the smallest positive number that can be expressed as the difference of two nonzero squares in more than two ways: , or . [1]
Issue 45 of The North Briton was thought to be seditious but its publisher, John Wilkes, was celebrated as a champion of liberty. The number 45 was used as a symbol of support for him. Banquets were held with a theme of 45 while many items were produced showing the number or featuring it in some way. For example, a wig was produced with 45 curls. [2]
Arithmetic is an elementary branch of mathematics that studies numerical operations like addition, subtraction, multiplication, and division. In a wider sense, it also includes exponentiation, extraction of roots, and taking logarithms.
The International Standard Book Number (ISBN) is a numeric commercial book identifier that is intended to be unique. Publishers purchase or receive ISBNs from an affiliate of the International ISBN Agency.
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A prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself. However, 4 is composite because it is a product (2 × 2) in which both numbers are smaller than 4. Primes are central in number theory because of the fundamental theorem of arithmetic: every natural number greater than 1 is either a prime itself or can be factorized as a product of primes that is unique up to their order.
In number theory, the Fermat pseudoprimes make up the most important class of pseudoprimes that come from Fermat's little theorem.
John Wilkes was an English radical journalist and politician, as well as a magistrate, essayist and soldier. He was first elected a Member of Parliament in 1757. In the Middlesex election dispute, he fought for the right of his voters – rather than the House of Commons – to determine their representatives. In 1768, angry protests of his supporters were suppressed in the Massacre of St George's Fields. In 1771, he was instrumental in obliging the government to concede the right of printers to publish verbatim accounts of parliamentary debates. In 1776, he introduced the first bill for parliamentary reform in the British Parliament.
A triangular number or triangle number counts objects arranged in an equilateral triangle. Triangular numbers are a type of figurate number, other examples being square numbers and cube numbers. The nth triangular number is the number of dots in the triangular arrangement with n dots on each side, and is equal to the sum of the n natural numbers from 1 to n. The sequence of triangular numbers, starting with the 0th triangular number, is
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92 (ninety-two) is the natural number following 91 and preceding 93
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A stem-and-leaf display or stem-and-leaf plot is a device for presenting quantitative data in a graphical format, similar to a histogram, to assist in visualizing the shape of a distribution. They evolved from Arthur Bowley's work in the early 1900s, and are useful tools in exploratory data analysis. Stemplots became more commonly used in the 1980s after the publication of John Tukey's book on exploratory data analysis in 1977. The popularity during those years is attributable to their use of monospaced (typewriter) typestyles that allowed computer technology of the time to easily produce the graphics. Modern computers' superior graphic capabilities have meant these techniques are less often used.
The North Briton was a radical newspaper published in 18th-century London. The North Briton also served as the pseudonym of the newspaper's author, used in advertisements, letters to other publications, and handbills.
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The Wilcoxon signed-rank test is a non-parametric rank test for statistical hypothesis testing used either to test the location of a population based on a sample of data, or to compare the locations of two populations using two matched samples. The one-sample version serves a purpose similar to that of the one-sample Student's t-test. For two matched samples, it is a paired difference test like the paired Student's t-test. The Wilcoxon test is a good alternative to the t-test when the normal distribution of the differences between paired individuals cannot be assumed. Instead, it assumes a weaker hypothesis that the distribution of this difference is symmetric around a central value and it aims to test whether this center value differs significantly from zero. The Wilcoxon test is a more powerful alternative to the sign test because it considers the magnitude of the differences, but it requires this moderately strong assumption of symmetry.
In number theory, a congruent number is a positive integer that is the area of a right triangle with three rational number sides. A more general definition includes all positive rational numbers with this property.
In the mathematical field of graph theory, the Hoffman–Singleton graph is a 7-regular undirected graph with 50 vertices and 175 edges. It is the unique strongly regular graph with parameters (50,7,0,1). It was constructed by Alan Hoffman and Robert Singleton while trying to classify all Moore graphs, and is the highest-order Moore graph known to exist. Since it is a Moore graph where each vertex has degree 7, and the girth is 5, it is a (7,5)-cage.
In mathematics, the values of the trigonometric functions can be expressed approximately, as in , or exactly, as in . While trigonometric tables contain many approximate values, the exact values for certain angles can be expressed by a combination of arithmetic operations and square roots. The angles with trigonometric values that are expressible in this way are exactly those that can be constructed with a compass and straight edge, and the values are called constructible numbers.
Single-precision floating-point format is a computer number format, usually occupying 32 bits in computer memory; it represents a wide dynamic range of numeric values by using a floating radix point.
