Question

If sin 115° ≈ 0.91 and cos 115° = -0.42, then sin -115° =

Answer 1

PLATO ANSWER

-0.91; -0.42

Explanation:

The sine function is an odd function, meaning that sin -x = -sin x. Because sin 115° ≈ 0.91, sin -115° ≈ -0.91.

The cosine function is an even function, meaning that cos -x = cos x. Because cos 115° = -0.42, cos -115° = -0.42.

Answer 2

sin -115° = -0.91

Explanation:

Point A is (cos 115°, sin 115°). Since cos 115° = -0.42 and sin 115° ≈ 0.91, it means that the coordinates at point A is (-0.42, 0.91).

As for point B which was revolved around -115°,

the coordinates will be similar to point A but you just have to change the negative.

B(cos -115°, sin -115°) = B(0.42, -0.91)