How does $(k+1)!(k+2)-1 = (k+2)!-1$?

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I'm trying to do a proof by induction question and I'm at the very last part. Apparently $(k+1)!(k+2)-1 = (k+2)!-1$. I have checked using an online calculator.

I don't understand why though.

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The recurrence for $n!$ is $n! = n (n-1)!.$ Apply for $n=k+2.$