Definitions of gamma function

1. Jul 15, 2009

LHS1

I spend some time studying special functions recently. I found two definitions of gamma function, one in form of integral and the other in form of infinite products, and I cannot prove of their equivalence. I found the definition in infinite product form important in proofing many properties of gamma function such as gamma reflection formula, therefore I eager to learn it. Could anyone help me, please !

2. Jul 15, 2009

Santa1

3. Jul 15, 2009

LHS1

Thank you very much!