Evaluate the triple integral where is the solid tetrahedon with vertices .
My question is, how do you find the equation of the plane z = ?
I need that to start solving the problem but i have no idea how to do that.
This is what it looks like to me: You need the equation of the gray plane in the figure below. To get it, you first calculate a normal which I've shown. Calculate the normal via the cross-product of two vectors which you can calculate emanating from the point (0,4,0). Once you get the normal, then the equation of the plane is
I'm not sure about this. Hopefully, this can get you in the ball-park.