-4cos480° = 4cos180°+300°180°+300°180°+300° = 4 cos300° = 4 * −0.866-0.866−0.866 ≈ -3.464
Итак, -4cos480° ≈ -3.464.
-4cos480° = 4cos180°+300°180°+300°180°+300° = 4 cos300° = 4 * −0.866-0.866−0.866 ≈ -3.464
Итак, -4cos480° ≈ -3.464.