What is lim_(->-oo) f(x) = absx/(16-x^2) ?

1 Answer
Nov 21, 2015

lim_(x rarr -oo)|x|/(16-x^2) = 0

Explanation:

Since we're dealing with -oo we can say |x| = -x, so

lim_(x rarr -oo)|x|/(16-x^2) = lim_(x rarr -oo)-x/(16-x^2)

Now, with that out of the way, factor out an x on the denominator
lim_(x rarr -oo)-x/(16-x^2) = lim_(x rarr -oo)x/(x(16/x - x))

Cancel the two xs otu

lim_(x rarr -oo) = 1/(16/x - x)

Now, because that 16/x will become a 0 in the limit, which will make the limit as a whole become a 0, or

lim_(x rarr -oo) 1/(0 - x) = lim_(x rarr -oo) 1/x = 0