Three identical masses are at the three corners of the triangle, connected by massless identical springs (rest length \( l_0 \)) forming an isosceles right angle triangle. If the two sides of equal length (of length \( 2l_0 \)) lie along the positive x-axis and positive y-axis, then the force on the mass that is not at the origin but on the x-axis is given by \( \hat{i} + \hat{j} \) with \( a \) and \( b \).