I can see how it works but how do i prove it?

[Chatt]

Homework Statement

[PLAIN]http://img708.imageshack.us/img708/8725/mathhelp.gif


I can kinda see that p(x) will be smaller than L1 and larger than Ln, but I have no idea of how to prove it. As a side note; p(x) is really the rayleigh quotient.

Please help, I sat up till very late last night, just looking at it without doing any progress :s

 

[lanedance]

for one way, how about trying replacing all the Li by Ln, noting Li>=Ln for all i?