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i had almost go there thanks

**ohlookabirdie**- Replies: 5

i have 3 Analysis questions whxch look simple to me, but for the life of me i cannot work out... i think i must just be being stupid, or having an off day :S, anyway they are as follows:

1) Use the triangle inequality to prove that for all *a*, *b* ∈ **R**,

|*a*-*b*| ≥ |*a*| - |*b*|.

2) Find the limit of Lim(√(*n*² + *n*) -*n*) from *n* to ∞.

(here i know the answer to be 1/2 but i dont know how to get it)

3) Use standard results to show that the function

*f*(*x*) = {*x*² for *x* ∈ (-∞,1), 1 for *x* ≥ 1}

is continuous on **R**.

(**R** is the real numbers, i dont know how to do the special R for it)

sorry if my formating is off, im not good with typing math

**ohlookabirdie**- Replies: 7

hey there, i discovered this site while checking if i had got a math problem right, google sent me here (all hail the mighty google, lord of the internet) and i found that i was correct.

desided that this was a good place for me to be so i subscribed and now im posting my first post to say hi and tell you all a bit about myself (whether you care or not)

first off, im not telling you my name, you can use may user name or call me 'cpm' or 'pyro'. these are nicknames i use on other websites (see the link in my sig for an example) and i still use because my new username cant be shortened to anything i like (please dont call me 'birdie')

secondly (because that is the logical next step after first, but im not getting into a philisophical discusion about the ordering of numbers here), i am a final year maths student at a university (oh secretively leaving out that detail )

and thirdly, i must shamelessly plug my photography. i am a wildlife photographer and you can find a link in my sig to a very good forum about birds, which is my speciality.

thank you for taking the time to read my drivle (i dont think that is how that is spelled but oh well)

~ohlookabirdie~

(a.k.a. cpm, a.k.a. pyro)

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