Quaternion.Slerp not rotating over 180 degrees unity code example

Example 1: unity rotation to quaternion

using UnityEngine;public class Example : MonoBehaviour
{
    void Start()
    {
        // A rotation 30 degrees around the y-axis
        Quaternion rotation = Quaternion.Euler(0, 30, 0);
    }
}

Example 2: unity rotate quaternion around axis

RoatationVar = Quaternion.Euler(Vector3.up) * camera.rotation;