Understanding Integration in Poisson's Equation

[yungman]

Homework Statement

Given:
y(x)=\int f(x)sinh(a-x)dx \;\;for\;\;0<x<a

Solve for y(x)


Convension way is:

y(x)=\int_0^x f(s) sinh(a-s)ds



But the book gave:

y(x)=\int_x^a f(s) sinh(s)ds

I don't see the connection.

 

[lanedance]

are there any other properties of y or f to use?

 

[yungman]

are there any other properties of y or f to use?

No. As you see, I am not looking for the solution. It is the way that I set up the equation is different from the book and I tried and cannot get the same answer.

This is a simplified version of a complicate Poisson's equation and I cannot agree with the book on the way how the book did on the change of variable.