If an angle θ is in SP and pt P(x,y) is a point on the terminal side of θ with r being the radius vector then the trig ratios of θ are defined as follows:

Sine θ = sin θ = y ÷ r Cosine θ = cos θ = x ÷ r Tangent θ = tan θ = y ÷ x Cotangent θ = cot θ = x ÷ y Secant θ = sec θ = r ÷ x Cosecant θ = csc θ = r ÷ y

r= radius vector r= √x^two + y^two or r^two= x^two + y^two

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