# How is DH and RSA used together in HTTPS? [duplicate]

I'm trying to get my head around how DH and RSA are used in HTTPS. I'm sorry if this is a duplicate.

I've done research into what RSA and DH are, but I'm trying to figure out how they are used together in HTTPS.

So, I've read RSA handles authentication. It uses a private/public key pair and can authenticate a server.

DH is a key exchange algorithm, and DHE is DH, but the agreed upon secret is thrown away after a certain time.

Does RSA handle the authentication, and encrpts the DHE process of agreeing upon a shared secret with which futher communication will be encrypted? If so, is the reason DHE is used because it allows to throw away the shared secret? Why not continue to use the RSA key pair to encrypt communication instead of agreeing upon a shared secret?

This probably contains some misunderstands etc, I'm not to well versed in this.