of Trigonometric Ratios
Trigonometric ratios depend only on the angle, not the size of the triangle. Similar triangles with the same angles have identical ratios!
For acute angles, sin θ and cos θ are always between 0 and 1, while tan θ can take any positive value.
Each trigonometric ratio has a reciprocal relationship: cosecant, secant, and cotangent are reciprocals of sine, cosine, and tangent respectively.
The fundamental identity sin²θ + cos²θ = 1 allows us to find all other ratios when one is known, using the Pythagorean theorem.