How can I use sin and cos for rotation

Okay, so this is my code:

float temp1 = Mathf.Cos(  (Input.mousePosition.x - Screen.width) / 2 );
float temp2 = Mathf.Sin( -(Input.mousePosition.y - Screen.height) / 2);
Camera.mainCamera.transform.parent.transform.Rotate(temp1, temp2, 0);

So I am trying to rotate the parent of my camera based on the angle between my mouse and the parent of the camera. Except I am doing something wrong can someone help me out its rotating in all kinds of random directions?

Thanks in advance!

Not 100 % what you’re asking for, but this should get your started…

using UnityEngine;
using System.Collections;

public class Rotate : MonoBehaviour {
	void Update () {
        Vector3 dir = new Vector3(Screen.width,Screen.height,0)*.5f;
	    dir = Input.mousePosition - dir;

	    float angle = Mathf.Atan2(dir.y, dir.x)* Mathf.Rad2Deg;

	    Camera.main.transform.eulerAngles= new Vector3(0, 0, -angle);
	}
}

The input to a sin and cos function is an angle, in radians. An input that flows between 0 and 2*pi will generate a full cycle. Your inputs are growing much higher than that, which is why it appears to be jumping around. You will need to scale the input into a fraction o screen size(or half screen size), then multiply by 2Pi (or Pi).