Is the Limit of a Continuous Function Equal to the Limit of its Variable?

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If a function f is continuous in a neighborhood around x = a, then the limit of f as x approaches a is equal to f evaluated at a. This is expressed mathematically as lim(x → a) f(x) = f(lim(x → a) x), which simplifies to lim(x → a) f(x) = f(a). The continuity of f at x = a ensures that both sides of the equation are equal. This relationship reinforces the concept of continuity in mathematical analysis. Thus, the limit of a continuous function at a point is indeed equal to the function's value at that point.
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If f is continuous in some neighborhood of x = a, then is the following true:

\lim_{x \rightarrow a} f(x) = f( \lim_{x \rightarrow a} x)?
 
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If f is continuous in some neighborhood of x = a, it is also continuous at x = a, because x = a is contained in the neighborhood. The l.h.s equals the r.h.s because of the fact that the limit as x tends to 'a' of f(x) equals 'f(a)' (because of continuity of f) and on the other hand, f of the limit of x as 'x tends to a' is obviously f(a) since lim(x) = a as x --> a
 
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JG89 said:
If f is continuous in some neighborhood of x = a, then is the following true:

\lim_{x \rightarrow a} f(x) = f( \lim_{x \rightarrow a} x)?

This an anorthodoxe way of writting : f is continuous at x=a <====>
\lim_{x \rightarrow a} f(x)=f(a)

But i suppose is correct since \lim_{x\rightarrow a}x = a
 
JG89 said:
If f is continuous in some neighborhood of x = a, then is the following true:

\lim_{x \rightarrow a} f(x) = f( \lim_{x \rightarrow a} x)?

That is true. This makes clear the idea of continuity.
 
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