Help with proving a sequence converges

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I am really stuck on this on

Let sn and tn be sequences. Suppose that lim sn = L (where s is a real number) and lim |sn - tn| = 0. Prove that lim tn = L.

I think this is going in the right way but i am not sure. If the lim an = A, then lim |an - A| = 0.

any help would be very nice.
 
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Help proving a sequesnce converges

I am really stuck on this on

Let sn and tn be sequences. Suppose that lim sn = L (where s is a real number) and lim |sn - tn| = 0. Prove that lim tn = L.

I think this is going in the right way but i am not sure. If the lim an = A, then lim |an - A| = 0.

any help would be very nice.
 
let N be so large that
|s_n|<epsilon/2
|s_n-t_n|<epsilon
what can you say about
|t_n|
?
hint
|A-B|<=|A|+|B|
 
I know how to do a N Epsilon proof but don't you have to have |s_n + t_n - (s + t)| < epsilon??

And that is to show that the lim (s_n + t_n) = s + t. I need to know lim |s_n - t_n| = 0. i guess i am unsure how the abs effect the proof.
 
I have merged the two threads.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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