Concepts inRemark on algorithm 723: Fresnel integrals
Fresnel integral
S(x) and C(x) The maximum of C(x) is about 0.977451424. If ¿t²/2 were used instead of t², then the image would be scaled vertically and horizontally (see below). ]] Fresnel integrals, S(x) and C(x), are two transcendental functions named after Augustin-Jean Fresnel that are used in optics.
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Integral
Integration is an important concept in mathematics and, together with its inverse, differentiation, is one of the two main operations in calculus. Given a function f of a real variable x and an interval [a, b] of the real line, the definite integral is defined informally to be the area of the region in the xy-plane bounded by the graph of f, the x-axis, and the vertical lines x = a and x = b, such that areas above the axis add to the total, and the area below the x axis subtract from the total.
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