This problem requires you to use the Coordinate Plane and/or the Unit Circle definitions of the trig functions. We did this extensively while reflecting the basic triangles over the axes to find the important points on the unit circle in all four quadrants. (Remember I kept asking you, “What’s the reference angle?”)
If the angle in given in degrees, continue to work in degrees (or you can switch to radians if you like). If a problem is given in radians, do not translate it to degrees! but stay in radian measure.
IMPORTANT: When you are asked to find exact values, it means you must not use your calculator to compute them: rather, in this problem, use your knowledge of the important points on the unit circle and draw a picture to explain your answer – that is how you show your work! You may also need to draw a picture of one of the two important right triangles. But if you show nothing at all and just write down the answer, you receive 0 points!
• WeBWorK UnitCircle (Use “Show Me Another” if you have already completed this.)
• Here are four videos from Patrick’s Just Math Tutorials which may be helpful: