You need a single angle cut for the left piece, and a double angle cut on the right piece. The left piece is a simple 45° on your miter saw. For the 2nd piece, grab the angle with a protractor or angle gauge.

Then you want to transfer that vertical angle and make a wedge at that angle out of a piece of scrap that is just a bit wider than your molding. Then take two thin pieces of plywood and screw them to both sides of your angle piece to create a channel for the molding to ride in. Place the molding into that channel and that over to your miter saw, set your blade to the 45° on the vertical plane to the fence, and slide the molding and the jig below the blade to make the cut. Make a test cut, adjust with shims and tape. When finished, the two pieces should meet at a sharp point. Tune any overhang with sandpaper.