Mathematics: Trigonometric Values Naturally, because this topic is trigonometry, there will be graphs related to it! In GCSE you will need to learn about three types of these trigonometric functions (basically means graphs). Theseare Sine (sin), Cosine (cos) and Tangent (tan) graphs (y = sinx , y = cosx , and y = tanx More on these graphs in chapter 8.8)! The number or value you will receive is on the y axis, and the angle in degrees is on the x axis. X is usually written as the greek alphabet θ (theta) so don’t stress when you see it! It just means angle! Normally, since you have a calculator, you just need to press the SIN/COS/TAN button and then input the angle after it and BOOM! The value pops up! However since you have a non-calc paper, your syllabus requires you to memorize the basic values of each graph. Here is a table that will help you memorize it! If you don’t believe what is on here, you can check with your calculator! These are all the values that you will have to memorize so be glad! However bad news is that they will come up quite often and you will need to know when to use them! Where do these values come from? Why do I have the exact value instead of the one with decimals shown on the calculator? Well that’s simple! It’s because of the Special Triangles! These two here are what they call the Special Triangles. These two cases are always true. The lengths of the triangle are only ratios, which is why they have no units. What this means is that if the length of one side doubles, the length of all the other sides will double given that the angles stay the same. With these triangles, you can already work out the trigonometric values of 30°, 45°, and 60°! Use SOH-CAH-TOA! See if you can do it!