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Parabolas, definition

This is a generalization of the case of a parabola, Eq. (9). It turns out to be a simple consequence of our three canonical rules. Using the definition of the tangent line in terms of a double root x0, we can write ... [Pg.119]

X (k < 0) and reside in regions I and II (y > 0, A > 0), which are sepa rated by parabola y /4 = A. In region I, the inequality y - 4A > 0 is additionally fulfilled and, consequently, = 0. For this reason, a minor deviation of the system from the initial point is inevitably followed by turning the system back (evolution) to the same point along curves plotted schematically in Figure 3.4. According to A. M. Lyapunov s definition, region I relates to stable nodes. [Pg.155]

The profile itself is strongly determined by the reorganization energy A which is by definition the energy of the product with respect to its equilibrium state when its solvent coordinate is still the same as that of the reactant state. If the curvatures of the reactant and the product parabolas are identical, the reorganization energy can also be defined as the work required to distort the reactant (D,A) from its equilibrium coordinate (Fig. 6.1) to the equilibrium coordinate qp of the product without any electron transfer (Fig. 6.1). [Pg.113]

For the exact determination of the specific charge, an a >paratus was constructed (J. J. Thomson) in which the ions are deliected in an electric field and a magnetic field parallel to it. If a photographic plate is set up perpendicular to the original direction of the rays, the image obtained on the plate is a family of parabolas (fig. 6, Plate I). By a simple calculation ( 1, p. 26) we can see tliat the points on a definite parabola arise from a definite set of particles with the same value of e/m and that the individual points of this parabola correspond to different velocities of the particles, in siidi a way in fact that the marks due to the particles with smaller velocities, and tlicrefore more easily deflected, are farther away from the vertex of the para-... [Pg.18]

Examples.—(1) A comet moves upon the parabolic path y z=4ax find its rate of approach to the sun which is placed at the focus of its orbit. Let r denote the distance from the focus to any point P(x, y) on the parabola. Hence, from the definition of a parabola r = x + a . drjdt = dxjdt. Or its rate of approach to the sun is the same as its horizontal velocity. Let s denote the length of the path, then dsjdt = velocity of motion = V, say. But by differentiation of the given equation,... [Pg.126]

Such parabolas represent a simple situation. The parabolas intersection point qc satisfies by definition Vpiqc) = Vp(qc). This gives ... [Pg.952]

We present the main results in Table 4.14 where the basic electronegativity and chemical hardness calculated by finite difference approximations in terms of IP and EA definitions are considered (Lackner Zweig, 1983). This is based on two positive arguments they are based on the Parr s DFT groimd state parabola method that is consistent with definition (4.234) of global electrophilicity electronegativity imder Mulliken... [Pg.293]

Under the hypothesis of a symmetric and positive definite matrix G, each onedimensional search can be approximated using a parabola with a minimum for the stationary point. [Pg.408]

Comparison of known experimental data of definition D above-stated phenols a method of crossed parabolas [3,18] with calculated in the present woik specifies (Fig. 2) that the closest are results in a case of use of approach PM6 about parameter RHF. [Pg.209]

Find the following area by computing the values of a definite integral. The area bounded by the parabola y = 4 - x and the x axis. You will have to find the limits of integration. [Pg.98]


See other pages where Parabolas, definition is mentioned: [Pg.359]    [Pg.354]    [Pg.53]    [Pg.10]    [Pg.1248]    [Pg.2009]    [Pg.15]    [Pg.21]    [Pg.245]    [Pg.108]    [Pg.108]    [Pg.590]    [Pg.31]    [Pg.118]    [Pg.257]    [Pg.129]    [Pg.129]    [Pg.314]   
See also in sourсe #XX -- [ Pg.15 ]




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