Question

A student claims that they can use rules about the coordinates of point A to tell wether the cosine of the angle formed by the x-axis and the kind that connects the origin to point A will equal a positive or a negative value. Which of the following statements supports the student’s claim?

A) if the y-coordinate is positive, the cosine will equal a positive charge.

B) if the x-coordinate are negative, the cosine will equal a negative value.

C) if the x-coordinate is in Quadrant l, the cosine will equal a negative value.

D) if the x- and y-coordinates are negative, the cosine will equal a positive value.

Answer 1

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Answer:

B) if the x-coordinate is negative, the cosine will equal a negative value

Explanation:

The cosine of the angle is the x-coordinate of the point where the terminal ray intersects the unit circle. Its sign will match the sign of the coordinates of point A on the terminal ray.

if the x-coordinate is negative, the cosine will be negative