What are the 3 trigonometric formulas?
Matthew Shields
Updated on March 17, 2026
What are the 3 trigonometric formulas?
The three main functions in trigonometry are Sine, Cosine and Tangent….Sine, Cosine and Tangent.
| Sine Function: | sin(θ) = Opposite / Hypotenuse |
|---|---|
| Cosine Function: | cos(θ) = Adjacent / Hypotenuse |
| Tangent Function: | tan(θ) = Opposite / Adjacent |
How do you find an angle using cosine?
Example
- Step 1 The two sides we know are Adjacent (6,750) and Hypotenuse (8,100).
- Step 2 SOHCAHTOA tells us we must use Cosine.
- Step 3 Calculate Adjacent / Hypotenuse = 6,750/8,100 = 0.8333.
- Step 4 Find the angle from your calculator using cos-1 of 0.8333:
How do you find the trigonometric value of an angle?
Since 360∘ represents one full revolution, the trigonometric function values repeat every 360∘. For example, sin360∘=sin0∘, cos390∘=cos30∘, tan540∘=tan180∘, sin(−45∘)=sin315∘, etc. In general, if two angles differ by an integer multiple of 360∘ then each trigonometric function will have equal values at both angles.
What is sin times cos?
The tangent of x is defined to be its sine divided by its cosine: tan x = sin x cos x . The cotangent of x is defined to be the cosine of x divided by the sine of x: cot x = cos x sin x .
How do you find sin given Cos?
The Basic Two: Sine and Cosine
- (1) Memorize: sine = (opposite side) / hypotenuse.
- (2) sin A = cos(90° − A) or cos(π/2 − A) cos A = sin(90° − A) or sin(π/2 − A)
- (3) Memorize:
- (4) tangent = (opposite side) / (adjacent side)
- (5) Memorize:
- (6) tan A = cot(90° − A) or cot(π/2 − A)
- (7) sec A = csc(90° − A) or csc(π/2 − A)
When to use sin cos tan?
In trigonometry, sin cos and tan values are the primary functions we consider while solving trigonometric problems. These trigonometry values are used to measure the angles and sides of a right-angle triangle . Apart from sine, cosine and tangent values, the other three major values are cotangent, secant and cosecant.
What is tan in terms of sin and cos?
Definitions: In the following definitions, sine is called “sin,” cosine is called “cos” and tangent is called “tan.” The origin of these terms relates to arcs and tangents to a circle.
How to find sin cos tan?
Sine θ = Opposite side/Hypotenuse = BC/AC
