second-order accurate central differences

Hi,

It is my first time here and I really need your help please :)

I have this equation:

Given

d^2T/(dx^2) - 1/(L-x) dT/dx - (2h(LW + bL- bx)(T-Tinfinty))/kbW(L-x) = 0

Where Tinfinity is 300K X is the coordinate measured along the fine k= 237 W/m/K h = 15 W/m^2/K L= 0.01 m W = 0.1 m b= 0.01 m T(x=0) = 1073 K

dT/dx |x=L = 0

The question:

the above question by second-order accurate central differences for the points in the middle in the ODE, and use three-point backward difference formula for the point at x = L. Show how you get the linear systems in details. To solve the linear systems, you can write your own code, such as Gauss-Seidel, or use Matlab built-in functions. Use L = 0.00999999 m for the length of the fin because x = L is a singular point of the ODE and the problem cannot be solved as specified. An approximate solution can, however, be obtained by using L = 0.00999999 m for the length of the fin. Divide the pin into 50 sub-intervals. Tabulate and plot your results using matlab or other tools, such as Excel.

Please answer me as soon as possible

Thank you in advance :)