The coordinates of the point on the unit circle that corresponds to an angle of 0º are

and

the coordinates of the point on the unit circle that corresponds to an angle of 90º are

ANSWER




EXPLANATION

a. We want to find the coordinates on the unit circle that corresponds to an angle of 0°

In general, the points on the unit circle are given by,



So we substitute,


to obtain,





b. For the coordinates of the point on the unit circle that corresponds to an angle of 90º,

We substitute

to obtain,



This simplifies to,

In all honesty, there really is no “work” per say to show. mainly it’s just using the process of elimination. the question is asking which domain(s) would be the most appropriate for the function c(n). n is the number of observed vehicles so right away, 1, 2, and 3 can be eliminated.why? 1, 2 start in the negatives and therefore it is impossible to observe negative cars. so, #4 would be the best answer to the given problem.