Question

how do you use a circle to find out what cos, tan, and sin is?

Answer 1

In the unit circle, the x value is cos, the y value is sin, and the slope of the line is tan.

Answer 2

I'm referring to the x and y values where the line intersects the circle.

Answer 3

For example, cos(90°) = 0 because that corresponds to the line being vertical.

Answer 4

One advantage of using the unit circle over using just any collection of triangles is that you can visualize when the values will be negative. Negative values is a big conceptual step in my opinion.

Answer 5

For example, cos(180°) = -1 because that corresponds to the line being horizontal and pointing to the left.