Tough Integration question. (1 Viewer)

shongaponga

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Hey guys just having some trouble with this question, any help is appreciated.
 

barbernator

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you can use an x=sec(theta) substitution to simplify. And then u can use a u=sin(theta) and it should be a simple integration from there.
 
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You can use a substitution after the simplification but it's not that necessary IMHO.

After the sub, you end up with . If we see patterns in the integrals of trigonometric functions, this is easy to integrate. . It can be deduced that . A similar relationship applies for and . These relationships are very useful when determining integrals of trig functions. It's very nice how you can 'co' all the functions and then put a minus sign out the front - if you know what I mean.

Additionally,



Looks similar to the trig identities?

+Cs, obviously.
 
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lolcakes52

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Just one correction. The integral of cot(x)csc(x) dx is -cosec(x) not cot(x) right?
 

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