I can't seem to figure out how to find this seemingly simple limit (that is shown numerically to go to 0)(adsbygoogle = window.adsbygoogle || []).push({});

lim_{x → ∞}( x r^{x})

for r < 1

This is an indeterminate form of∞ * 0, but when I try to apply L'Hôpital's rule as

lim_{x → ∞}( r^{x}/ ( 1 / x ) )

I end up getting an expression of the formx, with further application of the rule generating higher and higher powers of^{2}r^{x}x

I'm totally stuck!

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# Help me find this limit!

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