Definition talk:RSA Algorithm

I don't understand how Fermat's little Theorem is being applied here. $y^b = (x^a \pmod M)^b$, but how is that equivalent to $x$? Is $ab$ prime or something? Where does the $\pmod M$ go? How is it using the fact that $ab = 1 \pmod K$? --HumblePi (talk) 14:50, 26 August 2021 (UTC)