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Please help with these questions-limits etc.

I've attached the questions, thank you so much in advance.

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Could you start the problems yourself?
let us know what you have tried, im sure people will want to help, but few would be okay with doing it for you
Reply 2
I require some assistance with 2,3,4. with 3 i think it is either b or f or both not sure though. Thanks
Reply 3
For question 3- For (b) i can show its less than for any n but not equal so not sure and same for (f) can show its greater than but not the equal part.
Original post by betapro
For question 3- For (b) i can show its less than for any n but not equal so not sure and same for (f) can show its greater than but not the equal part.


So what did you do for 3 (b)?
Original post by betapro
For question 3- For (b) i can show its less than for any n but not equal so not sure and same for (f) can show its greater than but not the equal part.


b and f are correct and the answer is 4 - the 'or equal to' part is unnecessary but used in all of them so you can ignore it - the statements are still true

what have you tried for 2&4?
Reply 6
I just tried tons of numbers for small n and large and always worked but cant find an n that it is equal or a way of showing mathematically that they are
Original post by betapro
I just tried tons of numbers for small n and large and always worked but cant find an n that it is equal or a way of showing mathematically that they are


Does this make any sense to you?
n1n2+1nn2+1\displaystyle \frac{n-1}{n^2+1} \le \frac{n}{n^2+1}
Reply 8
Yes, where from there?
Reply 9
oh and then u get rid of 1 and then get 1/n
Reply 10
So then B is correct right? what about f
Original post by betapro
So then B is correct right? what about f


Difference of squares?
Reply 12
Original post by MathMoFarah
b and f are correct and the answer is 4 - the 'or equal to' part is unnecessary but used in all of them so you can ignore it - the statements are still true

what have you tried for 2&4?


Yes for 2 i got 6) so L=1 and not a clue how to do 4 :biggrin:
Original post by betapro
Yes for 2 i got 6) so L=1 and not a clue how to do 4 :biggrin:


your 2 is right

you have to manipulate things for 6 until you get something that HAS to follow the inequality
i.e. a higher denominator and lower numerator always guarantees a lower number
Reply 14
Original post by MathMoFarah
your 2 is right

you have to manipulate things for 6 until you get something that HAS to follow the inequality
i.e. a higher denominator and lower numerator always guarantees a lower number


For problem 6 i got 5 as my answer? How do u do q4 or is that what u were talkikng about?
Reply 15
Original post by EricPiphany
Difference of squares?


So would you agree that it is b and f correct for q3?
Original post by betapro
For problem 6 i got 5 as my answer? How do u do q4 or is that what u were talkikng about?


How did you get 5 though?
Reply 17
Original post by EricPiphany
How did you get 5 though?


Found values for which absolute values vanish and split into three intervals and then tested each one
Original post by betapro
So would you agree that it is b and f correct for q3?


Yes.
Reply 19
Original post by EricPiphany
Yes.


Great thanks :biggrin: Have you had a look at q4? I am currently doing it, also did u get same answers for 6 then?

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