Integration Techniques: (lesson 4 of 4)

## Trigonometric Substitutions

Use trigonometric substitution to evaluate integrals involving the
radicals,

### Case I:

Example 1:

Solution:

Then,

Example 2:

Solution:

Let x = 2 sin θ, dx = 2 cosθ dθ

### Case II:

Example 3:

Solution:

Then,

### Case III:

Example 4:

Solution:

Then,

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## Random Quote

Go down deep enough into anything and you will find mathematics.

Dean Schlicter

## Random Quote

I like mathematics because it is not human and has nothing particular to do with this planet or with the whole accidental universe - because like Spinoza's God, it won't love us in return.

Bertrand Russell