Table of Contents This is part of a tutorial series on the CKKS homomorphic encryption scheme. In the last article, we described the ciphertext-ciphertext addition and multiplication operations. We ended with two challenges, one to restore the squared scaling factor $\Delta^2$ back to $\Delta$, and the other to convert a three-tuple ciphertext (decrypting under $(1, s, s^2)$) back to a two-tuple ciphertext (decrypting under $(1, s)$). This article covers the latter challenge, which is called relinearization.