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**(sorry the thread title is wrong - can a mod please change it to "Limit of e^-7x cos x?")**

1. Homework Statement

1. Homework Statement

Find the following:

[tex]\lim_{x \rightarrow \infty} e^{-7x} \cos x[/tex]

## Homework Equations

I know that [tex] [ \lim_{x \rightarrow a} f(x)g(x) ] = [ \lim_{x \rightarrow a} f(x) ] \cdot [ \lim_{x \rightarrow a} g(x)] [/tex] so...

## The Attempt at a Solution

From the above equations...

[tex][\lim_{x \rightarrow \infty} e^{-7x} \sin x] = [(\lim_{x \rightarrow \infty} e^{-7x}) \cdot (\lim_{x \rightarrow \infty} \cos x)][/tex] But this limit DNE, since [tex]\lim_{x \rightarrow \infty} cos x : DNE[/tex]

And yet, WebAssign tells me that DNE is wrong, and that I must use the Squeeze Theorem for this problem. Any help? My trig is a little rusty (last time I took it was 9 years ago), so any useful reminders on that front would be helpful as well. I'm taking Calc I.