Как использовать RSA для шифрования ключей AES?

Нашёл тут пример данного кода, но не могу понять как правильно записать RSAEncrypt и RSADecrypt чтобы он принимал массив байтов AESKeyAndIV, подскажите.

static public Tuple<byte[], byte[]> EncryptAES(byte[] toEncryptAES, RSAParameters RSAPublicKey)
    {
        byte[] encryptedAES = null;
        byte[] encryptedRSA = null;

        using (MemoryStream ms = new MemoryStream())
        {
            using (RijndaelManaged AES = new RijndaelManaged())
            {
                AES.KeySize = 256;
                AES.BlockSize = 128;
                AES.Mode = CipherMode.CBC;
                AES.GenerateIV();
                AES.GenerateKey();
                encryptedRSA = RSAEncrypt(AES.Key, RSAPublicKey);

                using (var cs = new CryptoStream(ms, AES.CreateEncryptor(), CryptoStreamMode.Write))
                {
                    ms.Write(AES.IV, 0, AES.KeySize); //DOESNT WORK HERE
                    //Can't use CS to write it to the stream else it will encrypt along with file
                    cs.Write(toEncryptAES, 0, toEncryptAES.Length);
                    cs.Close();
                }
                encryptedAES = ms.ToArray();
            }
        }
        return new Tuple<byte[], byte[]>(encryptedAES, encryptedRSA);
    }
    static public byte[] DecryptAES(byte[] toDecryptAES, byte[] AESKeyAndIV, RSAParameters RSAPrivateKey)
    {
        byte[] AESKey = RSADecrypt(AESKeyAndIV, RSAPrivateKey);

        using (MemoryStream ms = new MemoryStream())
        {
            using (RijndaelManaged AES = new RijndaelManaged())
            {
                AES.KeySize = 256;
                AES.BlockSize = 128;
                AES.Key = AESKey;
                ms.Read(AES.IV, 0, AES.KeySize); //Not sure if can read MS here
                AES.Mode = CipherMode.CBC;

                using (var cs = new CryptoStream(ms, AES.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    //Would I need to move 0 to 256?
                    cs.Write(toDecryptAES, 0, toDecryptAES.Length);
                    cs.Close();
                }
                return ms.ToArray();
            }
        }
    }