# Category Archives: Integration Techniques

### Integration Application: Area of Rectangles and Area under the Curve

This is a common type of question which involves using rectangles of equal width to estimate the area under the curve. There are two ways to draw the rectangles. One way will give you an underestimate of the exact area while the other way will give you an overestimate. In this question, both ways are explored and we zoom in on the approach of how to prove the total area of n number of rectangles is expressed in summation form.   ### Differential Equation Definitions & Problem

The main challenge in Differential Equation is formulating a differential equation from a problem situation and deriving its solution. It requires basic integration techniques as shown in the following question.   ### Integration by Parts Formula Derivation & Examples

When students start learning Integration by Parts, they might not be able to remember the formula well. In fact, you do not need to rote memorise if you know that Integration by Parts can be derived in seconds from Differentiation Product Rule and I highly recommend you to do so via Product Rule until it comes to you naturally.

In this post, I show you the step by step to derive your Integration by Parts formula and examples to apply it.   