How do you find lim t/sqrt(4t^2+1) as t->-oo?

1 Answer
Dec 12, 2016

-1/2 (See below)

Explanation:

For t != 0, we have

t/sqrt(4t^2+1) = t/sqrt(t^2(4+1/t^2))

= t/(sqrt(t^2)sqrt(4+1/t^2))

We know that sqrt(t^2) = abst, so for t < 0, we have

= t/(-t(sqrt4+1/t^2))

= (-1)/sqrt(4+1/t^2)

As trarroo, the ration 1/t^2 rarr0, so we get

lim_(xrarr-oo) t/sqrt(4t^2+1) = lim_(xrarr-oo) (-1)/sqrt(4+1/t^2)

= (-1)/sqrt(4+0) = -1/2