ISI Consumer Theory 2010 Sample Paper

[TheFlash]

I am confused about the approach to the B part of Q9 of ISI sample paper 2010. Please help. Thanks.

[Asd1995]

If (x1,x2) is a solution then so is (x2,x1) as both utility and budget constraint are symmetric in x1,x2 (hence, lagrangian optimisation conditions give you that all critical points are symmetric) so maximum will also be symmetric.

If it is unique then only possibility is x1=x2