# CIE A Level Maths: Pure 3复习笔记5.1.8 Integration Decision Making

### Decision Making

#### What is meant by integration and decision making?

• The hardest part of integration is deciding which technique to use
• There are lots of them!

#### How do I know which integration method to use?

• The main two requirements for success with integration are
• Experience
• Familiarity
• Always check for Reverse Chain Rule …
• … particularly after changing part of an integral …
• … by using a trig identity for example

Key to diagram above:

#### Exam Tip

• If in doubt, try something … You may gain marks for attempting a suitable substitution.
• You may gain marks from using a trig identity.
• You may gain marks from attempting to simplify or rewrite a fraction.