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Maths help

Help with the following question please
(edited 2 months ago)
Reply 1
Original post by adrianunigo
Help with the following question please

What have you tried? The symmetry in the problem should give a hint about one common factor.
(edited 2 months ago)
Reply 2
Original post by mqb2766

What have you tried? The symmetry in the problem should give a hint about one common factor.


Can you explain further please I’ve attempted this 5 times
Reply 3
Original post by adrianunigo
Can you explain further please I’ve attempted this 5 times

If there was no +/-8s in the expression, so
a^4-b^4 / a^3-b^3
could you spot a common factor (factor theorem)? Then how can this be modified when you consider the original expression.
Reply 4
Original post by mqb2766

If there was no +/-8s in the expression, so
a^4-b^4 / a^3-b^3
could you spot a common factor (factor theorem)? Then how can this be modified when you consider the original expression.


I’m still a bit lost, could you tell me the answer and how you got to it? I’ve got to submit it before 1pm. Thanks
Reply 5
Original post by adrianunigo
I’m still a bit lost, could you tell me the answer and how you got to it? I’ve got to submit it before 1pm. Thanks

For the simplified expression, you should see subbing a=b makes both the numerator and denomiantor zero so that means both have a factor (a-b) which can be cancelled. Then think how that can be modified for the actual question.
Reply 6
Original post by mqb2766

For the simplified expression, you should see subbing a=b makes both the numerator and denomiantor zero so that means both have a factor (a-b) which can be cancelled. Then think how that can be modified for the actual question.


Yeah it should cancel to a-b/1 but I don’t know how to modify it for the actual expression?
Reply 7
Original post by adrianunigo
Yeah it should cancel to a-b/1 but I don’t know how to modify it for the actual expression?

It does not cancel to that expression as there is only a single common factor.
The question is all about spotting a (common) factor using the factor theorem so its worth having a read through your notes, trying some (other) simplified questions. So what if the exponents smaller ...
Reply 8
Ok I’ll do that, do I need to expand the brackets?
Reply 9
Original post by adrianunigo
Ok I’ll do that, do I need to expand the brackets?

Take the hint about thinking about a simpler (smaller exponent) problem to try and spot the factor first. Or if you were solving numerator = 0 or denominator = 0, what is the solution, what is the common factor, ...
(edited 2 months ago)
Reply 10
Original post by mqb2766

Take the hint about thinking about a simpler (smaller exponent) problem to try and spot the factor first. Or if you were solving numerator = 0 or denominator = 0, what is the solution, what is the common factor, ...


Can I show you what I’m doing in dms? I’m actually in uni, this is a topic we haven’t been taught, we’re just expected to finish quizzes using a level knowledge, I posted in this subreddit because I’m doing foundation year
Reply 11
Original post by adrianunigo
Can I show you what I’m doing in dms? I’m actually in uni, this is a topic we haven’t been taught, we’re just expected to finish quizzes using a level knowledge, I posted in this subreddit because I’m doing foundation year

Tbh, Ive given about all the hints I can without simply giving you the common factor, and the previous hint about when is (both) the numerator = 0 and denominator = 0 pretty much gives it away. If you cant solve this, just post your attempt, but its almost gcse knowledge to get that part, then a bit of messy division/factorisation to get the actual A and B required.
Reply 12
Original post by mqb2766

Tbh, Ive given about all the hints I can without simply giving you the common factor, and the previous hint about when is (both) the numerator = 0 and denominator = 0 pretty much gives it away. If you cant solve this, just post your attempt, but its almost gcse knowledge to get that part, then a bit of messy division/factorisation to get the actual A and B required.


All I’m asking for is the answer
Original post by adrianunigo
All I’m asking for is the answer

Nobody is just going to give you the answer, and you should know better than to ask for it.
Reply 14
Original post by Veet Voojagig

Nobody is just going to give you the answer, and you should know better than to ask for it.


Thanks veet

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