Find the displacement of the wedge when `m` comes out of the wedge. There is no friction anywhere.

Explanation

Let wedge move towards right by distance `x` then
`/_\x_(CM)=(m(lcostheta+x)+Mx_m(x-l))/(m+M+m)`
`0=mlcostheta-ml(m+M+m)x`
`x=(ml-mlcostheta)/(2m+M)`