Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 3 - No. 28)
If the length of the adjacent side to a 30-degree angle is 5, what is the approximate length of the hypotenuse?
2.5
5.77
10
8.66
説明
cos(30°) = 5/Hypotenuse, Hypotenuse = 5/cos(30°) = 5 / 0.866, approximately 5.77