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Calculus/Integration techniques/Irrational Functions
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Integration techniques/Reduction Formula Integration techniques/Numerical Approximations
Integration of irrational functions is more difficult than rational functions, and many cannot be done. However, there are some particular types that can be reduced to rational forms by suitable substitutions.
Type 1
Integrand contains
Use the substitution .
Example
Find .
Find .
Type 2
Integral is of the form
Write as .
Example
Find .
Type 3
Integrand contains , or
This was discussed in "trigonometric substitutions above". Here is a summary:
For , use .
For , use .
For , use .
Type 4
Integral is of the form
Use the substitution .
Example
Find .
Type 5
Other rational expressions with the irrational function
If , we can use .
If , we can use .
If can be factored as , we can use .
If and can be factored as , we can use
Integration techniques/Reduction Formula Integration techniques/Numerical Approximations