Mariah Carey's back -- and she's nailing those high notes left and right.

TMZ obtained footage of the powerhouse vocalist's full Las Vegas dress rehearsal (because of course they obtained footage of her first Las Vegas dress rehearsal) and homegirl is werkin'. it. out.

The clip (which you can feast your ears on above) features spliced audio from MC's rehearsal at The Colosseum at Caesar's Palace earlier this week, and Mariah hits every vocal mark, from the steady belt in "Hero" to her unbelievably high-pitched range in "Emotions." Our personal favorite is the fan who audibly yells "YAASSS" as soon as Mariah hits the first one. We feel you, guy.

While Mariah is famous for her beyond impressive five-octave vocal range, sadly, she's been making more headlines this year for her off-key performances, prompting many (okay, maybe just us) to wonder if she was having some kind of vocal cord issue. Whatever the case may be, it certainly looks like it was resolved -- just in time for her to kick off her Las Vegas residency and perform at the 2015 Billboard Music Awards for the first time in a whopping 17 years. Word on the street (or word on Showbiz411, at least) is that Mariah will sing "Vision of Love," which will "bleed into" her latest single, "Infinity," the site reports. Eek!

And did we mention that Mariah is dropping a greatest hits album, #1 to Infinity, on May 18? Things are certainly falling back into place for MiMi, and we couldn't be happier for her.

Live on, Mariah Carey's five-octave vocal range. Live on.

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