This topic studies the derivative formula of function and the properties of extreme point. The idea of solving the problem is: first, take the derivative of the function and get the derivative of the original function. Then, according to the known conditions of the topic, when x= 1, the value of the derivative function is 0, and the one-dimensional linear equation about a is obtained. The value of a can be obtained by solving the equation.

Knowledge points that can be accumulated in this question: 1, derivative formulas of some commonly used functions (need to be accumulated at ordinary times)

2. The nature of derivative function: when the function is at the extreme point, its derivative function value is 0.

The specific problem solving process is as follows, I hope it will help you.