# L'hospital's Rule

• Oct 21st 2009, 03:16 PM
mlckb1
L'hospital's Rule
I'm supposed to be finding the limit of a function using L'hospital's Rule but with this limit:

limit (as x goes to infinity) of (e^x)/(x^3)

I just can't see how L'hospital's Rule applies since the numerator is going to infinity while the denominator is going to zero(Wondering) But the answer in the back of the book is infinity, so i think I'm looking at it wrong. Can someone explain to me how L'hospital's Rule applies?
• Oct 21st 2009, 03:19 PM
skeeter
Quote:

Originally Posted by mlckb1
I'm supposed to be finding the limit of a function using L'hospital's Rule but with this limit:

limit (as x goes to infinity) of (e^x)/(x^3)

I just can't see how L'hospital's Rule applies since the numerator is going to infinity while the denominator is going to zero(Wondering) But the answer in the back of the book is infinity, so i think I'm looking at it wrong. Can someone explain to me how L'hospital's Rule applies?

try again ... as $\displaystyle x \to \infty$ , $\displaystyle x^3 \to \, ?$
• Oct 21st 2009, 03:56 PM
mlckb1
Quote:

Originally Posted by skeeter
try again ... as $\displaystyle x \to \infty$ , $\displaystyle x^3 \to \, ?$

Oh i see it now (Sun) thank you!