It's different. Integral substitution is a very effective method to solve problems. For some mathematical problems with complex structure and many variables, some new variables are introduced to simplify their structures. Its method of substitution can simplify the complex and turn the difficult into the easy, so as to find a shortcut to solve the problem. Therefore, the integral replacement method is different from method of substitution. Changing the method is to replace a condition, a data or a keyword in the original math problem and make it a new problem.