Learn the sine, cosine and tangent ratios of sides of a right triangle and how to identify the opposite, adjacent and hypotenuse sides using SOHCAHTOA. See examples, practice problems and a video lesson on the sine ratio. Learn how to calculate sine, cosine and tangent of any angle using the formula soh s ine = o pposite / h ypotenuse, soh cah c os = a djacent / h ypotenuse, soh toa t an = o pposite / a djacent. See examples, practice questions and a memory trick for sohcahtoa. We know that sin, cos, and tan are the reciprocals of cosec (or csc), sec, and cot functions. Thus, we can derive 3 more formulas related to sin, cos, and tan. sin A = 1/csc A (or) csc A = 1/ sin A. cos A = 1/sec A (or) sec A = 1/cos A. tan A = 1/cot A (or) cot A = 1/tan A. .

sin cos tan rules