A question about limits
Maths and statistics discussion, revision, exam and homework help.
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Re: A question about limitsI will show that(Original post by anonstudent1)
Why does [x+y]<= [x] + [y]
equal
[x]-[y]<=[x+y]
where [x] is the modulus/absolute value of x
and 
are equivalent. First, set 
in to obtain 
. Then, set in to obtain 
.
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Re: A question about limits[a]<=[x]-[b](Original post by Hopple)
Rewrite x+y as a, and y as -b, and see what comes out.
[x]+[b]<=[a] -
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Re: A question about limitsOk i get i understand now. Thanks for your help!(Original post by Hopple)
x = a+b, and |-b| = |b|
Also, how did you get from the first line of that to the second? 
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Re: A question about limitsWait sorry i don't understand lol(Original post by Hopple)
x = a+b, and |-b| = |b| Also, how did you get from the first line of that to the second?
Ok so i get
[a]<= [a+b] - [b]
How do i go from there to get
[a+2b] <= [x]+[y]
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Re: A question about limitsnohomo's basically written it all out, but doing as I said, you'll get the first inequality becoming |a| <= |a+b| + |b|(Original post by anonstudent1)
Wait sorry i don't understand lol
Ok so i get
[a]<= [a+b] - [b]
How do i go from there to get
[a+2b] <= [x]+[y]
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Re: A question about limitsThank you!(Original post by nohomo)
I will show that and are equivalent. First, set in to obtain . Then, set in to obtain .
Also, how did you get from the first line of that to the second? 
