The solvability of a system of nonlinear equations
Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (2021), pp. 3-10.

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It is proved: if $\phi(\tau,\xi)$ is scalar continuous real function of arguments $\tau\in [a_{(n-1)},\ b_{(n-1)}]\subset R^{n-1},\ \xi\in [a,\ b]\subset R^{1}$ and $\phi(\tau,a) \phi(\tau,b)0\ \forall \tau, $ then for each $\varepsilon >0$ exists a continuous $\phi_{0}(\tau,\xi),$ that $|\phi(\tau,\xi)- \phi_{0}(\tau,\xi)|\varepsilon $ and the equation $\phi_{0}(\tau,\xi)=0$ has continuously depends on $\tau$ solution. The statement is suitable to a proof of a solvability finite system nonlinearity equations, to an estimation of a number of solutions. We give illustrating examples.
Mots-clés : equation
Keywords: smallest solution, non uniqueness of solution.
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V. S. Mokeychev. The solvability of a system of nonlinear equations. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (2021), pp. 3-10. http://geodesic.mathdoc.fr/item/IVM_2021_1_a0/

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