定积分的计算是高考中一个基本考点,常见的计算方法有定义法、几何意义法与微积分基本公式法等。高中阶段,由于定义法求定积分(四个基本步骤:分割、近似代替、求和、取极限)过程比较烦琐,实际计算中不太实用。在实际应用中,一般利用几何意义法、微积分基本公式法、定积分性质法以及被积函数奇偶性法等来计算求解。1.几何意义法 The calculation of definite integral is one of the basic test centers in college entrance examination. The common calculation methods are definition method, geometric meaning method and calculus basic formula method. In high school, due to the definition of integral (four basic steps: segmentation, approximate replacement, summation, take the limit) process is cumbersome, the actual calculation is not practical. In practice, the general use of geometric meaning calculus method, the basic principle of integral calculus method, and the integrand function parity method to calculate the solution. 1. Geometrical meaning of law