How to solve the equation \(AuBu+Cu=f\). (English) Zbl 1051.47009

Li, Chun-li; Cui, Ming-gen

Appl. Math. Comput. 133, No. 2-3, 643-653 (2002).

The authors discuss the problem of solving the initial value problem \[ AuBu+Cu=f, \quad u(0)=1 \tag{1} \] where \(f, u\in W(\Omega)\), \(A,B,C\in L(W(\Omega))\), where \(W(\Omega)\) is the reproducing kernel space on the subset \(\Omega\) of \(\mathbb{R}^1\) and \(L(W(\Omega))\) is the space of continuous linear operators from \(W(\Omega)\) into \(W(\Omega)\).
The authors use the method to transform a one-dimensional nonlinear operator equation into a two-dimensional linear operator equation. To achieve these results, they firstly discuss the problem how to solve a continuous linear operator equation in a separable Hilbert space. If the solution exists, there is given the representation and approximation of the minimal normal solution of the equation and formula are obtained. Further on, there is given a factorization method and characteristic value method to solve equation (1).

Reviewer: Muhib Lohaj (Prishtina)

MSC:

47A50	Equations and inequalities involving linear operators, with vector unknowns
65J15	Numerical solutions to equations with nonlinear operators

Keywords:

operator equation; reproducing kernel; nonlinear operator

References:

[1]	Aronszain, N., Theory of reproducing kernels, Trans. am. math. soc., 68, 337-404, (1950) · Zbl 0037.20701
[2]	Cui, M., Two-dimensional reproducing kernel and surface interpolation, J. comp. math., 4, 2, 177-181, (1986) · Zbl 0617.41007
[3]	Kress, R., Linear integral equations, (1989), Springer Berlin