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Please help me with this, I am not sure what to do.

Please help me with this, I am not sure what to do.-example-1
User Martin Booka Weser
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1 Answer

14 votes
14 votes

Since
x is approaching 1 from the left/below, we take the part of
f(x) that is defined over
x<1, for which we have


f(x) = (x-1)/(√(x-1))

Since
x\\eq1, we can simplify this to


f(x) = (x-1)/((x-1)^(1/2)) = (x-1)^(1/2) = √(x-1)

and this is continuous at
x=1, so we can evaluate the limit by directly substituting
x.

To summarize:


\displaystyle \lim_(x\to1^-) f(x) = \lim_(x\to1) (x-1)/(√(x-1)) = \lim_(x\to1) √(x-1) = √(1-1) = \boxed{0}

User Jumhyn
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2.2k points