The homotopy analysis method is developed in 1992 by Liao [1]-[8]. It is an analytical approach to get the series solution of linear and nonline arpartial differential equations. The difference with the other perturbation methods is that this method is independent of small/large physical parameters. It also provides a simple way to ensure the convergence of series solution [9]. This method has been successfully applied to solve many linear and non linear partial differential equationsin various fields of science and engineering by many authors [1]-[16]. The homotopy analysis method is useful and efficient for obtaining both analytical and numerical approximations of linear or nonlinear differential equations. In this study, we will concentrate on exact solutions for equations type of and frequently used in applied and engineering mathematics.

We refer to the problem given by Partridge and Brebbia [17]. Consider the following engineering equations

where, that is, considered to be a known function of position and will be considered as a known function of the potential.

In all applications, the domain bounded by the ellipse given in Figure 1 will be used. The boundary condition is the Dirichlet condition with on the boundary.

The equation of the ellipse is

We apply the HAM to equations of the type and with Dirichlet boundary con- dition. We consider the following differential equation

where is a linear operator, and are independent variables, is an unknown function. In HAM, the zeroth-orderde formation equation is constructed as

where

is an auxiliary parameter, is an initial guess, is an auxiliary parameter and is the embedding parameter. Applying the homotopy-derivative [4]

To both sides of Equation (5), we get the following mth-order deformation equation

where

And

Note that for can be obtained by solving the linear Equation (8) with linear boundary conditions that come from original problem. If the power series Equation (6) of converges at, then we gets the following series solution:

We apply Homotopy Analysis Method to equations of the type and, as follows:

Equation (1) suggests that we define an equation of linear operator as

And Equation (2) suggests that we define an equation of linear operator as

Using the above definitions, the zeroth-orderde formation equation is constructed as

Applying the homotopy-derivative to the zeroth-orderde formation equation, we obtain the following mth- orderde formation equations

Since, , now the solution of the mth-orderde formation equation becomes

where

Example 1. Consider the equation of the type

With initial guess

using HAM, were cursively obtain

When, we obtain the exact solution as follows:

Example 2. Consider the equation of the type

with initial guess

using HAM, were cursively obtain

When, we obtain the exact solution as follows:

Example 3. Consider the equation of the type

with initial guess

using HAM, were cursively obtain

For, we obtained the closed form series solution as

which is the exact solution.

Example 4. Consider the equation of the type

with initial guess

using HAM, were cursively obtain

For, we obtained the closed form series solution as

which is the exact solution.

Example 5. Consider the equation of the type

with initial guess

using HAM, were cursively obtain

For, we obtained the closed form series solution as

which is the exact solution.

In this paper, the homotopy analysis method has been applied to solve some of engineering problems defined on an elliptical domain. Exact solutions for equations of the type and are obtained using the HAM. Obviously for the obtained solutions are as the same Reference [17]. There sults show that HAM is very efficient technique in finding the exact solutions for equations of the type and having wide applications in engineering mathematics.

Selcuk Yildirim, (2015) Homotopy Analysis Method for Equations of the Type ∇²=b(x,y) and ∇²u=b(x,y,u). Journal of Applied Mathematics and Physics,03,391-398. doi: 10.4236/jamp.2015.34049