Question on calc midterm

A group of Vassar students find themselves in a totally mathematical environment in R4 and wish to party. The "partying mood" of this group at any point (x,y,z,w)elementR4 is given by the differentiable function P(x,y,z,w)=x2+4y2+2z+sqrt2w2. The group is currently at (1,1,1,2sqrt2) (perhaps Rocky 300 in 4-space?). In which direction should this group move from (1,1,1,2sqrt2) in order to maximize their partying mood as quickly as possible?