Mr. Unit Circle

The unit circle is a very useful tool. It has a radius of 1, and shows the x and y values along the circumference. Using special case angles, we can find the lengths and values of right triangles that have one of the special angles. Again, cosine and sine come into play, as cosine=x value, and sine=y value. We can use the acronym ASTC, all students take calculus, which helps remember which function is positive in which quadrant. A is all, S is sine, T is tangent, and C is cosine. We made our own unit circles in class using paper plates, and we drew all the angles and also radian measures on them. This was very useful on the test, and saved lots of time!