Is the Limit Definition of Continuity Equivalent to the Standard Definition?

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The discussion centers on the equivalence of two definitions of continuity in calculus. The standard definition states that continuity at a point a is defined by lim x->a f(x) = f(a). An alternative expression, lim h->0 (f(x+h) - f(x)) = 0, is also considered valid, as it indicates that values near f(x) are close to f(x) itself. Participants confirm that both definitions are acceptable, provided f(x) exists. This clarification aids in understanding continuity in mathematical problems.
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Hey guys,

Continuity is generally expressed as lim x->a f(x)=f(a).
But is it also correct to express it as: lim h->0 f(x+h) - f(x) = 0?
Because that would imply that all numbers around f(x) would have to be very close to f(x), and that is basically what continuity is, no?
 
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Freye said:
Hey guys,

Continuity is generally expressed as lim x->a f(x)=f(a).
But is it also correct to express it as: lim h->0 f(x+h) - f(x) = 0?
Because that would imply that all numbers around f(x) would have to be very close to f(x), and that is basically what continuity is, no?

Yes, this is fine (assuming f(x) exists)
 
Ok thank you, it really helps me out on a problem I am working on.
 
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