Sine, Cosine and Tangent (often shortened to sin, cos and tan) are each a ratio of sides of a right angled triangle: For a given angle θ each ratio stays the same no matter how big or small the triangle is. To calculate them: Divide the length of one side by another side

In trigonometry, trigonometric identities are equalities that involve trigonometric functions and are true for every value of the occurring variables for which both sides of the equality are defined. Geometrically, these are identities involving certain functions of one or more angles.

Basic trig identities are formulas for angle sums, differences, products, and quotients; and they let you find exact values for trig expressions.

The sine and cosine of an acute angle are defined in the context of a right triangle: for the specified angle, its sine is the ratio of the length of the side opposite that angle to the length of the longest side of the triangle (the hypotenuse), and the cosine is the ratio of the length of the adjacent leg to that of the hypotenuse.

In trigonometry formulas, we will learn all the basic formulas based on trigonometry ratios (sin,cos, tan) and identities as per Class 10, 11 and 12 syllabi. Also, find the downloadable PDF of trigonometric formulas at BYJU'S.

Sin, cos, and tan functions in trigonometry are defined in terms of two of the three sides (opposite, adjacent, and hypotenuse) of a right-angled triangle. Here are the formulas of sin, cos, and tan. sin θ = Opposite/Hypotenuse. cos θ = Adjacent/Hypotenuse. tan θ = Opposite/Adjacent.

For a right triangle with an angle θ : Sine Function: sin (θ) = Opposite / Hypotenuse. Cosine Function: cos (θ) = Adjacent / Hypotenuse. Tangent Function: tan (θ) = Opposite / Adjacent. When we divide Sine by Cosine we get: So we can say: That is our first Trigonometric Identity.

When we find sin cos and tan values for a triangle, we usually consider these angles: 0°, 30°, 45°, 60° and 90°. It is easy to memorise the values for these certain angles. The trigonometric values are about the knowledge of standard angles for a given triangle as per the trigonometric ratios (sine, cosine, tangent, cotangent, secant and cosecant).

Sin and Cos are basic trigonometric functions along with tan function, in trigonometry. The sine of an angle is equal to the ratio of the opposite side to the hypotenuse whereas the cosine of an angle is equal to the ratio of the adjacent side to the hypotenuse.

Sin and Cos are basic trigonometric functions that tell about the shape of a right triangle. SO let us see the sin cos formula along with the other important trigonometric ratios. \(\sin θ= Perpendicular/ Hypotenuse\) \(\cos θ= Base/ Hypotenuse\) \(\tan θ= Perpendicular/Base\) \(\csc θ= Hypotenuse/Perpendicular\) \(\sec θ = Hypotenuse/Base\)