Definition: Tangent of a Real Variable

Let \(x\in\mathbb R\) be any real number. The tangent of \(x\) is a function \(\tan:\mathbb R\mapsto\mathbb R\) defined as the ratio of the sine and cosine of $x$, formally,

$$\tan(x):=\frac{\sin(x)}{\cos(x)}.$$

The tangent function has is demonstrated in the following figure:

  1. Proposition: Additivity Theorem of Tangent
  2. Proposition: Derivative of Tangent

Propositions: 1 2 3


Thank you to the contributors under CC BY-SA 4.0!

Github:
bookofproofs


References

Bibliography

  1. Forster Otto: "Analysis 1, Differential- und Integralrechnung einer Veränderlichen", Vieweg Studium, 1983