ON THE ULAM-HYERS STABILITY OF BIHARMONIC EQUATION

In this paper we investigate the Ulam-Hyers stability of the biharmonic equation in the class of circular symmetric functions. Biharmonic equation has many applications, for example in elasticity, fluid mechanics and many other areas. We apply our results in elasticity and civil engineering. We consider a circular plane plate. In this case the solutions will be functions with circular symmetry. In general the unknown functions are u = u (r, theta) but in the case of the circular symmetry u = u (r). The biharmonic equation Delta(2)u = p/D becomes r(4) d(4)u/dr(4) + 2r(3) d(3)u/dr(3) - r(2) d(2)u/ dr(2) + r du/dr = r(4) p/D; where p is the normal pressure load to the plate and D is the flexural rigidity.