Question

can someone please help me
evaluate
lim 3xe^-x
x->∞

Answer 1

Do you know L'Hopital's Rule?

Answer 2

a bit. how would I start it though

Answer 3

Your limit is equal to \(\displaystyle \lim_{x\to\infty}\dfrac{3x}{e^x}\), right?

Since direct substitution will get you \(\dfrac{\infty}{\infty}\) form, you can apply L'Hopital's Rule:

\[\lim_{x\to\infty}\dfrac{3x}{e^x} = \lim_{x\to\infty}\dfrac{3}{e^x}\]

Answer should be clear now.

Answer 4

yes

Answer 5

okay thanks :)