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The domain (input values) of the cosine function is all negative and positive angle measures.
Let the function be f(x) = cos(x)
The domain of cos(x) is -∞ < x < ∞
The range is -1 ≤ f(x) ≤ 1
Hence, domain of cos(x) is all (+) and (-) angle measures.
Same goes with sine function as well
For function f(x) = sin(x)
The domain is -∞ < x < ∞ and range -1 ≤ f(x) ≤ 1
However for f(x) = tan(x) the same is not applicable.
Answer:
A. all negative and positive angle measures.
Step-by-step explanation:
The domain of a function is the set of input values (x-values).
The cosine function is a continuous function, and therefore has no restrictions throughout its domain.
Therefore, its domain is all real numbers.
Set notation: { x | x ∈ R }
Interval notation: (-∞, ∞)