Question

limit as x approaches negative infinity of ((x^2)(e^x))

Answer 1

using l'hopital's rule

Answer 2

This requires l'Hopital's rule.

Write \[\frac{x^2}{e^{-x}}\]
Then have at it, twice.

Answer 3

derivative twice?

Answer 4

use l'Hoptal's rule, twice. You'll see. Try and use it once an you still have something tricky to deal with, so you need to use it again.

Answer 5

so i get 2/-e^-x so 0?

Answer 6

yes

Answer 7

what about limit as x approaches pi/4 of (1-tanx)(sec x)

Answer 8

New question, new post. But this limit is easy, surely, as tan x and sec x are defined and continuous at x = pi/4.