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Trigonometry2D

Hyperbolic Trigonometry - Theory & Concepts - Trigonometry Hyperbolic Functions

Comprehensive study of Hyperbolic Sine, Cosine, Tangent, and their relationships to the hyperbola and exponential functions.

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Circular vs. Hyperbolic Functions

Compare the unit circle x2+y2=1x^2+y^2=1 and the unit hyperbola x2y2=1x^2-y^2=1. Observe how the parameters represent sector areas.

1. The Unit Circle

Equation: x2+y2=1x^2 + y^2 = 1
Angle / Parameter (tt)1.00 rad (57°)
0.00π (~3.14)2π (~6.28)
COORDINATES(0.540, 0.841)
SECTOR AREAA = 0.500
x=cos(t)=0.540x = \cos(t) = 0.540y=sin(t)=0.841y = \sin(t) = 0.841
Circular functions trigonometric visualization on a unit circleP(cos t, sin t)

2. The Unit Hyperbola

Equation: x2y2=1x^2 - y^2 = 1
Hyperbolic Parameter (uu)1.00
-2.0002.00
COORDINATES(1.543, 1.175)
SECTOR AREAA = 0.500
x=cosh(u)=1.543x = \cosh(u) = 1.543y=sinh(u)=1.175y = \sinh(u) = 1.175
Hyperbolic functions visualization on a unit hyperbola

Exponential Formulations for Hyperbolic Functions

While circular functions are defined using trigonometric angles on a circle, hyperbolic functions are defined algebraically using exponents eue^u and eue^{-u}. Geometrically, both represent twice the area of their respective sectors.

Hyperbolic Cosine:
cosh(u)=eu+eu2\cosh(u) = \frac{e^u + e^{-u}}{2}
Value: cosh(1.00)=2.718+0.3682=1.5431\cosh(1.00) = \frac{2.718 + 0.368}{2} = 1.5431
Hyperbolic Sine:
sinh(u)=eueu2\sinh(u) = \frac{e^u - e^{-u}}{2}
Value: sinh(1.00)=2.7180.3682=1.1752\sinh(1.00) = \frac{2.718 - 0.368}{2} = 1.1752
Hyperbolic Tangent:
tanh(u)=sinh(u)cosh(u)=eueueu+eu\tanh(u) = \frac{\sinh(u)}{\cosh(u)} = \frac{e^u - e^{-u}}{e^u + e^{-u}}
Value: tanh(1.00)=1.1751.543=0.7616\tanh(1.00) = \frac{1.175}{1.543} = 0.7616