### Introduction

A
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partial differential equation
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(PDE) is a differential equation involving partial derivatives of one dependent variable with respect to two or more independent variables. The independent variables may be space variables only or one or more space variables and time. Mathematical modelling of many situations involving natural phenomena leads to PDEs.

The subject of PDEs is a very large one. We shall discuss only a few special PDEs which model a wide range of applied problems.

#### Prerequisites

- be able to carry out partial differentiation
- be able to solve constant coefficient ordinary differential equations

#### Learning Outcomes

- verify solutions of given partial differential equations arising in engineering and science