168k views
4 votes
Find the exact value of cos(570°).

A. -1
B. 0
C. 1
D. Undefined

User Kuza
by
8.1k points

1 Answer

4 votes

Final answer:

The exact value of cos(570°) is found by considering the periodicity of the cosine function and simplifying to cos(210°), which is -√3/2. There's no match among the provided options.

Step-by-step explanation:

The question asks to find the exact value of cos(570°). To find this, we can use the fact that the cosine function is periodic with a period of 360°. Therefore, cos(570°) is equivalent to cos(570° - 360°), which simplifies to cos(210°). The cosine of 210° is in the third quadrant where the cosine values are negative, and since 210° is 30° more than 180°, cos(210°) = -cos(30°). The cosine of 30° is √3/2, so cos(210°) = -√3/2. Therefore, the exact value of cos(570°) is -cos(30°) or -√3/2, which is none of the provided options A, B, C, or D.

User Rherroral
by
8.0k points

Related questions

asked Oct 16, 2019 157k views
Helper asked Oct 16, 2019
by Helper
7.6k points
2 answers
2 votes
157k views
2 answers
4 votes
89.6k views