precal question

Question

Find the terminal point P(x, y) on the unit circle determined by the given value of t.

t = 5π/6

 

P(x, y) =

 

 

Answer 1

Hi Viviana,

If the angle given is 5pi/6, we know this is in the second quadrant and it has a reference angle of pi/6. We're looking for the x and y coordinates on the unit circle where the angle terminates. On the unit circle, x coordinates are cosine values and y coordinates are sine values. In the second quadrant, sine values are positive, but all over trig functions are negative. You can use a unit circle or the relationship of special right triangles to figure out:

cos(5pi/6) = -√3 / 2

sin(5pi/6) = 1/2

So, the point is (-√3 /2, 1/2)

Hope this helps!

Hannah