Search results
Results from the WOW.Com Content Network
f-number. Diagram of decreasing apertures, that is, increasing f-numbers, in one-stop increments; each aperture has half the light-gathering area of the previous one. An f-number is a measure of the light-gathering ability of an optical system such as a camera lens. It is calculated by dividing the system's focal length by the diameter of the ...
One radian is defined as the angle subtended from the center of a circle which intercepts an arc equal in length to the radius of the circle. [6] More generally, the magnitude in radians of a subtended angle is equal to the ratio of the arc length to the radius of the circle; that is, =, where θ is the magnitude of the subtended angle in radians (= angle/rad), s is arc length, and r is radius.
Also, some fractions (such as 1 ⁄ 7, which is 0.14285714285714; to 14 significant figures) can be difficult to recognize in decimal form; as a result, many scientific calculators are able to work in vulgar fractions or mixed numbers.
Aspect ratio (image) The aspect ratio of an image is the ratio of its width to its height. It is expressed as two numbers separated by a colon, width:height. Common aspect ratios are 1.85:1 and 2.40:1 in cinematography, 4:3 and 16:9 in television, and 3:2 in still photography.
A method analogous to piece-wise linear approximation but using only arithmetic instead of algebraic equations, uses the multiplication tables in reverse: the square root of a number between 1 and 100 is between 1 and 10, so if we know 25 is a perfect square (5 × 5), and 36 is a perfect square (6 × 6), then the square root of a number greater than or equal to 25 but less than 36, begins with ...
Long division. In arithmetic, long division is a standard division algorithm suitable for dividing multi-digit Hindu-Arabic numerals (positional notation) that is simple enough to perform by hand. It breaks down a division problem into a series of easier steps. As in all division problems, one number, called the dividend, is divided by another ...
A. 1685. Graph of the equation y = 1/x. Here, e is the unique number larger than 1 that makes the shaded area under the curve equal to 1. The number e is a mathematical constant approximately equal to 2.71828 that is the base of the natural logarithm and exponential function.
From January 2008 to December 2012, if you bought shares in companies when Karl J. Krapek joined the board, and sold them when he left, you would have a -42.7 percent return on your investment, compared to a -2.8 percent return from the S&P 500.