Based on the features of unimodal function, select a practical value of an independent variable within the entire value range of the unimodal function; then, evaluate the function and conduct a reverse calculation of the function value; if there is a unique solution, make a new value range using the solution; carry on this calculation until we obtain the extreme value of the function. Compared with the Fibonacci method and the 0.618 method, bisection method is simpler and more effective.