COSH

Syntax COSH (x)
Location Hyper, Hyperbola

This function is defined very similarly to SINH. It can be expressed as:

( EXP(x) + EXP(-x) ) / 2

Example

The COSH function can be used to describe a rope, chain or similar object which has two ends tied at the same height to a ceiling (for instance). Line 110 draws the ceiling, lines 120 to 160 the chain.

100 a = .8: SCALE 10, -5, 0: CLS
110 LINE -2,CHAIN(-2) TO 2,CHAIN(2)
120 FOR x = -2 TO 2 STEP .1
130   y = CHAIN(x)
140   IF x > -2 THEN LINE _x, _y TO x, y
150   _x = x: _y = y
160 END FOR x
170 :
180 DEFine FuNction CHAIN(x)
190  RETurn a * COSH(x/a)
200 END DEFine CHAIN

CROSS-REFERENCE

See SINH for an example.

ARCOSH is the inverse function of COSH.