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The number π (/paɪ/; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although ...
Viète. de Moivre. Euler. Fourier. v. t. e. In trigonometry, trigonometric identities are equalities that involve trigonometric functions and are true for every value of the occurring variables for which both sides of the equality are defined. Geometrically, these are identities involving certain functions of one or more angles.
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The Falcon HTV-1 program, which preceded the Falcon HTV-2 program, was conducted in April, 2010. The mission ended within nine minutes from launch. Both these missions are funded by the US Defense Advanced Research Projects Agency (DARPA) to help develop hypersonic technologies and to demonstrate its effectiveness. Under the original plan, HTV-1 wa...
Development of protection structures that are tough and lightweight; an aerodynamic shape that has a high lift to drag ratio; automatic navigation control systems were among the initial technical challenges facing the designers. The various departments involved in designing the vehicle included aerothermodynamics, materials science, hypersonic navi...
Both flights reached Mach 20 (high-hypersonic speed) and lost telemetry at 9 minutes of a planned 30-minute mission. The HTV-2's first flight was launched on 22 April 2010. The HTV-2 glider was to fly 4,800 miles (7,700 km) across the Pacific to Kwajalein at Mach 20. The HTV-2 was boosted by a Minotaur IV Lite rocket launched from Vandenberg Air Fo...
DARPA does not plan to conduct a third flight test of the HTV-2. The decision was made because substantial data was collected from the first two flights, and a third was not thought likely to provide any additional valuable data for the cost. The first flight provided data in aerodynamics and flight performance, while the second provided informatio...
Wireless network technologies. In telecommunications, 5G is the fifth-generation technology standard for cellular networks, which cellular phone companies began deploying worldwide in 2019, and is the successor to 4G technology that provides connectivity to most current mobile phones. Like its predecessors, 5G networks are cellular networks, in ...
The plains-wanderer is a quail -like ground bird, measuring 15 to 19 centimetres (5.9 to 7.5 in). The adult male is light brown above, with fawn-white underparts with black crescents. The adult female is substantially larger than the male, and has a distinctive white-spotted black collar.
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics with the major subdisciplines of number theory, [1] algebra, [2] geometry, [1] and analysis, [3 ...
The 828-metre (2,717 ft) tall Burj Khalifa in Dubai has been the tallest building since 2010. The Burj Khalifa has been classified as megatall. A diagram showing the tallest buildings as of 2024 This is a list of the tallest buildings.Tall buildings, such as skyscrapers, are intended here as enclosed structures with continuously occupiable floors and a height of at least 340 metres (1,120 ft).
