Integration is the inverse of differentiation. Even though derivatives are fairly straight forward, integrals are not. Some integration problems require techniques such as substitution, integration by parts, trigonometric substitutions, or possibly more than one method. We will walk you through slowly, starting with the basic integration rules: the constant multiplication rule, the power rule, and the sum rule.

Some common functions you should get familiar with (we’ll show you more later):

\int a dx = ax + C
\int x dx = \frac{x^2}{2} + C
One more thing to remember, always add the constant of integration C.

Let’s start with the Power Rule:

\int x^n dx = \frac{x^{n+1}}{n+1} + C,\quad n\ne-1
The power rule simply tells you to divide by n+1 (the power + 1) and increase the power by 1, it’s that simple. Here’s an example of how it works (

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Let’s continue with the constant multiplication rule (

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\int af(x) dx = a\int f(x)dx
The constant multiplication rule simply tells to take out the constant

Moving on to the Sum Rule (

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Putting it all together (

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That wasn’t too bad. If you’d like to take a pick at some more advanced integrals

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Cheers,

Michal