Question

Unit circle help on question 3 ( attachment below)

Answer 1

use x= cos(angle) and y= sin(angle)
you probably should have memorized the angles they show, but you can use a calculator
(however a calculator gives a decimal number, and they might want the exact values)

example: cos(30) (the x value for angle 30º (or pi/6 radians) = sqr(3) / 2
but a calculator will give 0.866...

Answer 2

Oh i see now . Thank you

Answer 3

so would the side lengths √3/2 for cos(30 and 1/2 for sin(30)?

Answer 4

yes. specifically the x side is √3/2 and the vertical side (the y side) is 1/2

Answer 5

okay, just had to make sure I was on the right track

Answer 6

I think the very top part, where they show a ¼ of a circle
they want you to find the base and height of each triangle
using "special triangles" i.e. 30-60-90 and 45-45-90
we also know the hypotenuse is always 1 (it's the radius of a unit circle)

so, for example, with a triangle with 30º, the y value = ½ the hypotenuse = ½
and the x value will be sqr(3) times the hypotenuse/2 = sqr(3)/2

then you use those values to fill in the the cos and sin values in the lower part