Rewriting a Trigonometric Expression In Exercises 27-34, write the expression as the sine, cosine, or tangent of an angle. 27. sin 60 cos 20 - cos 60' sin 20" 28. sin 1 10 cos 65 + cos 1:10 sin 650 tan 325 - tan 116 tan 154 - tan 490 29. 30. 1 + tan 325 tan 116 1 + tan 154 tan 490 IT 31. cos COS sin sin 4 4 32. sin 9 COS + cos 9 sin 33. sin 3.5x cos 1.2y + cos 3.5x sin 1.2y 34. cos 0.78y cos 0.42z - sin 0.78y sin 0.42z