- #1
Pete.Co.Lust
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Homework Statement
I want to 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
Homework Equations
|x-4|<delta delta>0
|x^3|<espilon espilon>0
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 don't know what I should do afterwards... Should I just Sub x=4 and then find out |(x^2+4x+16)|<48?
Plx help me :( ThX! :)