Handbook of mathematics for engineers and scienteists part 195 pptx

... self-similar solution of the form w = t –2/3 U(z), where z = t –1/3 x. 8 ◦ . Solution: w(x, t)=2ϕ(z)+2C 1 t, z = x + 6C 1 t 2 + C 2 t, where C 1 and C 2 are arbitrary constants, and the function ϕ(z) ... 0, ∂F ∂t +  ∂ ∂x + ∂ ∂y  3 F = 0 generates a solution of the Korteweg–de Vries equation in the form w =–2 d dx K(x, x; t), where K(x, y; t) is a solution of the linear Gel’fand–Le...

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... equations of a curve. Parametric equations of a curve on the plane have the form x = ϕ(t), y = ψ(t), (4.2.1.4) where x and y are treated as the coordinates of some point A for each value of the ... coordinate system OXY has the form x a + y b = 1,(4.3.1.13) where a and b are the x-andy-intercepts of the line, i.e., the signed distances from the points of intersection of th...

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... directions of principal axes and of their conjugate chords are called the principal directions of a second-order curve. The angle between the positive direction of the axis OX and each of the two ... roots λ 1 and λ 2 of the characteristic equation (4.4.5.4) are the eigenvalues of the real symmetric matrix [a ij ] and, as a consequence, are real. Obviously, the invariants...

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... the surface that is formed by points of both surfaces in (4.5.2.18) and does not contain any other points. 4.6. Line and Plane in Space 4.6.1. Plane in Space 4.6.1-1. Equation of plane passing through ... z 0 ) and perpendicularly to a vector N =(A, B, C)hastheform A(x – x 0 )+B(y – y 0 )+C(z – z 0 )=0,or(r – r 0 ) ⋅ N = 0,(4.6.1.1) where r and r 0 are the position vectors of th...

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... series ∞  n=0 kx k–1 can be obtained from the left-hand side of the second formula in (8.3.3.7) for m = 0 and n = 1. Substituting S(x)=1/(1 – x) into the right-hand side of that formula, we get ∞  k=0 kx k–1 = d dx 1 1 ... subtraction, multiplication, and division of power series. 1. Addition and subtraction of power series.Twoseries ∞  n=0 a n x n and ∞  n=0 b n x n wit...

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... = 1; z p and C are arbitrary constants; and the a j (j ≥ 3) are uniquely defined in terms of α, β, z p ,andC. 2 ◦ . Two solutions of equation (12.3.4.8) corresponding to different values of the ... z p and C are arbitrary constants; the coefficients a j (j ≥ 7) are uniquely defined in terms of z p and C. 2 ◦ . In a neighborhood of a fixed point z = z 0 , the solution of the Ca...

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... the above holds for α = 1, 2, and β = 0,–1,–2, 14.4. Method of Separation of Variables (Fourier Method) 14.4.1. Description of the Method of Separation of Variables. General Stage of Solution 14.4.1-1. ... Derivation of equations and boundary conditions for particular solutions. The approach is based on searching for particular solutions of equation (14.4.1.1) in th...

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... constant, for some k and m. Transformation (15.3.4.2) is a combination of a translation transformation in t and scaling transformations in x and w. It should be emphasized that these transformations ... differential equations. 15.5. Method of Generalized Separation of Variables 15.5.1. Structure of Generalized Separable Solutions 15.5.1-1. General form of solutions. The clas...

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... 15.5. Algorithm for the construction of exact solutions by a nonclassical method for second-order evolution equations. Here, ODE stands for ordinary differential equation and PDE for partial differential equation. which ... condition of compatibility of equations (15.10.1.4) and (15.10.1.5). The compatibility condition is a differential equation for ϕ(y)andisa consequence...

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... operators of (15.10.2.4) in which the partial derivatives w t , w xx , w xt ,andw tt must be expressed in terms of x, t, w,andw x with the help of relations (15.10.2.12) and (15.10.2.2) and those ... to t and (15.10.2.2) with respect to t and x, and then equating the resulting expressions of the third derivatives w xtt and w ttx to one another: D t F =D x [D t G]. (15.10.2...

Ngày tải lên: 02/07/2014, 13:20