Is there enough information?

[natski]

Hi, I have been thinking recently about integrating something with 3 parts such as:

I=\int_{0}^{\infty}f(x)\ast g(x)\ast h(x)\ast dx

If I is an unknown that we are trying to find and we know what J and K are where:

J=\int_{0}^{\infty}f(x)\ast g(x)\ast dx

and

K=\int_{0}^{\infty}f(x)\ast h(x)\ast dx

Is there enough information to find I? (Note how we cannot get rid of or change the limits).

Natski

[natski]

Just to add, we assume that each function is easy to differentiate or integrate by itself but the three functions multiplies is too difficult.

Natski

[StatusX]

If your question is, can you express I in terms of J and K for arbitrary f,g,h, the answer is no. One easy was to see this is by letting f=1. You can still integrate by parts if you use something like u=f(x)g(x), du=h(x)dx.