Proof of Square Root Limit Theorem for Continuous Functions

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SUMMARY

The discussion focuses on proving the Square Root Limit Theorem for continuous functions, specifically stating that if \( f: A \to \mathbb{R} \) is a continuous function with \( f(x) > 0 \) for all \( x \in A \), then the limit of the square root of \( f(x) \) as \( x \) approaches \( c \) equals the square root of the limit of \( f(x) \) as \( x \) approaches \( c \). This is expressed mathematically as \( \lim_{x \to c} [f(x)^{1/2}] = [\lim_{x \to c} f(x)]^{1/2} \). The proof relies on the continuity of the square root function and the definition of limits.

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square root limit proof

R is the real nmbers

so let A be in R
let f: A -> R be such that f(x)>0 for all x in A
c is in A

Does anyone know the proof to or even get me started on this proof shown below

[It's hard to write roots on the computer, so I will use the 1/2-th power instead.] SO i want to prove the following

lim x ->c [f(x)^(1/2)] = [lim x->c f(x)]^(1/2),
PROVIDED f(x) > 0
 
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Use the continuity of the square root and the definition of limit.
 
In other words, this function, f, has very little to do with the question. The definition of "h(x) is continuous at x=a" is lim(x->a) f(x)= f(a). In this case, what is a?
 

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