There are being studied two minimisation methods used in optimisation of several changeable functions without limitation in this work, made their theoretical analysis, comparison of effectiveness and the results achieved during current research generalized. In the first part of work it is defined the optimisation concept as well as introduction of task is formulated. There is presented the importance of optimisation and meaning of task function in the optimisation process. The optimisation object and methods of classificaion are introduced. It is explained the importance of methods without limitations. There is detailed analysis of two minimisation methods (Nelder-Mid and Kvazi-Niuton), which are being applied in optimisation by several changeable functions without limitations, the methods’ algoritmic realisations are provided. In the second part is made short review of MatLab and Optimization Toolbox. It’s presented modern optimisation algorithms realised by Optimization Toolbox. The detail analysis of fminsearch and fminnunc MatLab functions is made, which are being realised by Nelder-Mid and Kvazi-Niuton methods. It’s being examined realisation methods of these functions as well as required parameters are defined. The third part is dedicated for the analysis of several changeable functions without limitations. It’s made scenarios of chosen methods of optimisation for graphical representation and studying. It’s taken few types of functions with two and three changeables... [to full text]