Integration Question (1 Viewer)

Ekman

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Hey,
I recently did my extension 1 exam and there was one hard integration question that seemed a bit weird.





EDIT: I know there is the log way of solving it, but keep in mind that this exam was also done with 2u students who haven't learnt what logarithms are yet...
 
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braintic

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One of the standard integrals given on the back of the paper is the integral of secxtanx. Substituting u = pi/2 - x allows you to integrate cosecxcotx using this rule.

secx and cosec x can be integrated using the t-results.

But Ext 1 students are not expected to come up with either of these substutitions - you are supposed to be fed the substitution.
 

PhysicsMaths

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I solved I by converting both to sinx and cosx, then letting u = sinx
 

Ekman

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I wasn't the issue, it was ii. As said by braintic, they should of built up the substitution for you in order to solve ii.
 

PhysicsMaths

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I wasn't the issue, it was ii. As said by braintic, they should of built up the substitution for you in order to solve ii.
They gave you nothing at all?
I'm pretty sure integrating cosecx is not required by the 3U syllabus
 

braintic

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I wasn't the issue, it was ii. As said by braintic, they should of built up the substitution for you in order to solve ii.
I know this is not an English forum, but you just wrote something that irks me every time I see it.
There is no such thing as "should of". It is "should have".
 

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