TRIGONOMETRY : CLASS 11 : CHAPTER 3 Different systems of angles, radian measure, degree, AB and CD formulas,  transformations of angles in different quadrants and solution of trigonometric equations Trigonometry: It is the branch of mathematics in which we deal with the relation between the angle and sides of the right triangle. Table 1 0 o 30 o 45 o 60 o 90 o 180 o 270 o 360 o Sin 0 1/2 \[1/\sqrt{2}\] \[\sqrt{3}/2\] 1 0 -1 0 Cos 1 \[\sqrt{3}/2\] \[1/\sqrt{2}\] 1/2 0 -1 0 1 Tan 0 \[1/\sqrt{3}\] 1 \[\sqrt{3}\] \[\infty\] 0 \[\infty\] 0 Cot \[\infty\] \[\sqrt{3}\] 1 \[1/\sqrt{3}\] 0 \[\infty\] 0 \[\infty\]