Using complex numbers for solving partial fractions (1 Viewer)

[mreditor16]

just a few questions from me -

Are we allowed to do so, first of all?

Is there ever a time when using it can lead to an incorrect answer?

And are there any strong reasons for or against using complex numbers in solving partial fractions?


thanks

 

[integral95]

just a few questions from me -

Are we allowed to do so, first of all?

Is there ever a time when using it can lead to an incorrect answer?

And are there any strong reasons for or against using complex numbers in solving partial fractions?


thanks

it actually can be used (done a few examples of those in uni) , but i doubt HSC would give such questions where you'd have to use complex numbers to solve partial fraction.

Wait, i dunno if the HSC allows this lol.

 

[glittergal96]

just a few questions from me -

Are we allowed to do so, first of all?

Is there ever a time when using it can lead to an incorrect answer?

And are there any strong reasons for or against using complex numbers in solving partial fractions?


thanks

Are we allowed: I don't see why not. If two polynomials are equal, then subbing a complex number into each should give you an equal output. This is certainly not out of syllabus.

Can it lead to an incorrect answer: Nope, see above.

Strong reasons for or against: Not really, but can you think of an example where using complex numbers is significantly shorter than any other method?

 

[mreditor16]

bumping!

 

[faisalabdul16]

Just use numbers

 

[tomnomnom696]

Simmons showed this method to his class so im pretty sure its allowed

 

[mreditor16]

Simmons showed this method to his class so im pretty sure its allowed

okay cool, thanks everyone

 

[IR]

Yeh, I figured this was your thread just by looking at the title.

 

[Immortality]

Complex numbers for partial fractions is fully legitimate, it is just that there is no real reason to do it for the HSC level.

 

[aDimitri]

we were taught to do this in class but it's slower than just comparing the coefficients

 

[mreditor16]

Just wondering how many people have learned the 3rd method for doing partial fraction after equating coefficients and substitution. The one that involves calculus. Because it is specifically mentioned in the syllabus.

I do not recall it. :/

 

[Drongoski]

I recall substituting i for (x^2+1) and the like from time to time when decomposing into partial fractions: no problems. Don't see why it's not legit.