# Hyperbolic Equations with Unknown Coefficients

## Abstract

**:**

## 1. Introduction

## 2. Statement of the Problem

**Inverse Problem I**: Find a function $u(x,t)$ and a number a that satisfy the equation:

**Inverse Problem II**: Find a function $u(x,t)$ and a number b such that they satisfy Equation (1) in the cylinder Q (for a given number a) and the function $u(x,t)$ enjoys conditions (2)–(5).

## 3. Solvability of Inverse Problems I and II

**Theorem**

**1.**

**Proof.**

**Theorem**

**2.**

**Proof.**

**Theorem**

**3.**

**Proof.**

## 4. Uniqueness of Solutions

**Theorem**

**4.**

**Proof.**

**Theorem**

**5.**

**Proof.**

## 5. Comments and Appendices

## Funding

## Conflicts of Interest

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Kozhanov, A.I.
Hyperbolic Equations with Unknown Coefficients. *Symmetry* **2020**, *12*, 1539.
https://doi.org/10.3390/sym12091539

**AMA Style**

Kozhanov AI.
Hyperbolic Equations with Unknown Coefficients. *Symmetry*. 2020; 12(9):1539.
https://doi.org/10.3390/sym12091539

**Chicago/Turabian Style**

Kozhanov, Aleksandr I.
2020. "Hyperbolic Equations with Unknown Coefficients" *Symmetry* 12, no. 9: 1539.
https://doi.org/10.3390/sym12091539