BComm vs Actuarial (UNSW vs MQ) (1 Viewer)

Pwnage101

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also works for ' (+/-infinity)/(+/-infinity) ' type limits

It is called 'l'hopital's rule'

and we can only l'hopital's rule use this when this limit f'(x)/g'(x) exists.

Wikipedia has an exellent example:

For example, if ƒ(x) = x + sin(x) and g(x) = x, then

lim x-->inf f'(x)/g'(x) = lim x-->inf (1+cosx)/1 which does not exist

which does not exist, whereas

lim x-->inf f(x)/g(x) = lim x-->inf (1+((sinx)/x)) = 1

In this case lim x-->inf f(x)/g(x) does NOT equal lim x-->inf f'(x)/g'(x).

Understanding is required to achieve good grades.
 

dvse

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Understanding is required to achieve good grades.
Most first/second year courses are taught at the level of symbolic manipulation - mechanically rewriting expressions following predefined rules. Most students have no idea what it may be taken to mean. Indeed this is a view shared by most lecturers - they don't teach in other ways because then it becomes too hard and there are too many complaints, as these are predominantly "service" subjects for engineers etc.
 
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Studentleader

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Most first/second year course are taught at the level of symbolic manipulation - mechanically rewriting expressions following predefined rules. Most students have no idea what it may be taken to mean. Indeed this is a view shared by most lecturers - they don't teach in other ways because then it becomes too hard and there are too many complaints, as these are predominantly "service" subjects for engineers etc.
The hardest question you'd get on L'Hopital's I'd believe would be derive it from first principals and I don't think that's ever been asked in the last 5 years of the unit in which L'Hopital's is proved.

Stuff like proving the mean value theorm is alright though because you can't write down the proof without knowing how it works.

I would have loved the look on everyone's face if they wrote 'Prove De Morgan's Law' in our second year discrete maths unit.
 

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