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44 votes
44 votes
Which angle is an x-intercept for the function y = cos(1)
A.0
B.2
C. £
D. 2£

Which angle is an x-intercept for the function y = cos(1) A.0 B.2 C. £ D. 2£-example-1
User Kosi
by
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1 Answer

17 votes
17 votes

Answer: C.
\pi

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Step-by-step explanation:

The x intercept always occurs when y = 0.

Use the unit circle to determine that
\cos(\theta) = 0 when
\theta = (\pi)/(2) \text{ and } \theta = (3\pi)/(2)

So if
x = \pi, then we have


y = \cos\left((1)/(2)x\right)\\\\y = \cos\left((x)/(2)\right)\\\\y = \cos\left((\pi)/(2)\right)\\\\y = 0\\\\

which shows us that
(\pi, 0) is the location of one of the infinitely many x intercepts for this function.

User Kylex
by
2.9k points