Laplace transformation of object's disruption signal is known. Disruption signal is described by operator equation F(s)=(s2+2·s+1)/((s+3)3·s2). Original of disruption signal's Laplace transformation has to be found. Original of Laplace transformation is in time domain. Formulas for basic Laplace transformations are being used. Heviside's formulas will be used to calculate factors of original function.