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Trigonometry Formulas
sin, cos, tan and triangle rules. · 7 formulas
Sine
sin θ = opposite / hypotenuseRight triangle ratio
Example
0.6
Cosine
cos θ = adjacent / hypotenuseRight triangle ratio
Example
0.8
Tangent
tan θ = opposite / adjacentRight triangle ratio
Example
0.75
Fundamental Identity
sin²θ + cos²θ = 1Core Pythagorean identity
Example
cos θ = 0.8
Area of Triangle (SAS)
A = ½ab sin CTwo sides and included angle
Example
10
Law of Sines
a/sin A = b/sin B = c/sin CSide over sine of opposite angle
Example
≈ 14.14
Law of Cosines
c² = a² + b² − 2ab cos CFind a side when two sides and included angle known
Example
≈ 6.24