Definition:Tangent/Trigonometry
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Definition
In the above right triangle, we are concerned about the angle $\theta$.
The tangent of $\angle \theta$ is defined as being $\dfrac{\text{Opposite}} {\text{Adjacent}}$.
Thus it is seen that the tangent is the sine over the cosine.
Sources
- Murray R. Spiegel: Mathematical Handbook of Formulas and Tables (1968): $5.3, \ 5.15$
