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kkk579

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how do i do this q? would i expect thus in y11ext1 cos ngo never taught us smth like this20240404_125048.jpg
 
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Aeonium

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moreos y12 adv
the long div part is less common and personally i just expand and add/subtract terms and then split fraction so it can cancel out
u could also work from the -x + 4 thing back to f(x) cause it seems easier (similar to how they can ask partial fraction in 2u ☠ just go the reverse)
oblique asymptote is technically 3u though but idt you need to worry about it bcz it's not rly too hard for these types of qns
for ii, just state as x—> infty the fraction goes to 0
 

kkk579

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moreos y12 adv
the long div part is less common and personally i just expand and add/subtract terms and then split fraction so it can cancel out
u could also work from the -x + 4 thing back to f(x) cause it seems easier (similar to how they can ask partial fraction in 2u ☠ just go the reverse)
oblique asymptote is technically 3u though but idt you need to worry about it bcz it's not rly too hard for these types of qns
for ii, just state as x—> infty the fraction goes to 0
how do u know to look at those specific x imtervals for iii tho? like i get that it comes from the quadratic but how do yk to do that?
 

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how do u know to look at those specific x imtervals for iii tho? like i get that it comes from the quadratic but how do yk to do that?
sign table — check in between the numbers in the brackets and left /right kf fhem if ykwim
 

kkk579

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Yeah i get that but why do we look specifically at that? how about the denominator?
Cos what about the other part of the graph? Wpuldnt that also be entirely negative? The part on the graph on the other side of the vertical asynptote
 

Aeonium

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Yeah i get that but why do we look specifically at that? how about the denominator?
ok so u can kinda ignore it tbh bcz it's a "bigger case" it's just like how in a quadratic which has 2 intercepts u know there's left centre and right
similar to you can use null factor theorum on the top brackets to get x intercepts
Cos what about the other part of the graph? Wpuldnt that also be entirely negative? The part on the graph on the other side of the vertical asynptote
uhh wdym
 

kkk579

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ok so u can kinda ignore it tbh bcz it's a "bigger case" it's just like how in a quadratic which has 2 intercepts u know there's left centre and right
similar to you can use null factor theorum on the top brackets to get x intercepts

uhh wdym
Like beyond the point x=5 wouldnt there be another geaph similar to the one already drawn but just upside down
 

kkk579

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ok so u can kinda ignore it tbh bcz it's a "bigger case" it's just like how in a quadratic which has 2 intercepts u know there's left centre and right
similar to you can use null factor theorum on the top brackets to get x intercepts

uhh wdym
wdym by bigger case?
 

Aeonium

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i thought we would do f(x)>0 and solve it like an inequality so like times both sides by (5-x)^2 and then continue with that
for this case sign table is much quicker bcz u can just consider the intervals
what i meant by 'bigger case' is for x < 5 the denominator is always positive so you can kind of ignore it in that area and for x > 5 the denominator will be negative
then considering the top case, have more intervals to consider
 

kkk579

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for this case sign table is much quicker bcz u can just consider the intervals
what i meant by 'bigger case' is for x < 5 the denominator is always positive so you can kind of ignore it in that area and for x > 5 the denominator will be negative
then considering the top case, have more intervals to consider
wait, what i did is correct right? its just that in thr sol they didnt consider the graoh beyond x=5
 

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wait, what i did is correct right? its just that in thr sol they didnt consider the graoh beyond x=5
yeah it'd work just it's intended to do sign table because it's already factorised
 

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