(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I wanna ask a question about Epsilon-Delta definition...

I have already read a tons of definitions about Epsilon-Delta limit proof. But i am still stucking in some places...

E.g.) Prove it by using Espilon-Delta method, lim (x->4) x^3=64

2. Relevant equations

|x-4|<delta delta>0

|x^3|<espilon espilon>0

3. The attempt at a solution

I am kinda know what I should do, I changed |x^3-64| into |(x-4)|(x^2+4x+16)| and my objective afterward is to ensure| (x^2+4x+16)| is "small".

But i just dunno what I should do afterwards... Should I just Sub x=4 and then find out |(x^2+4x+16)|<48?

Plx help me :( ThX!! :)

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# Homework Help: Help! Espilon-Delta limits

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