Seven divide by twice a number

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

Use the graph to determine the range. which notations accurately represent the range? check all that apply. (–∞, 2) u (2, ∞) (–∞, –2) u (–2, ∞) {y|y ∈ r, y ≠ –2} {y|y ∈ r, y ≠ 2} y < 2 or y > 2 y < –2 or y > –2

Which of the following points is collinear with (-2,1) and (0,3)