Funciones hiperbolicas
Funciones hiperbólicas


De la misma forma que las razones trigonométricas seno y coseno son funciones de una variable real con la propiedad

sen 2 (x)+ cos 2 (x)=1 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaae4CaiaabwgacaqGUbWaaWbaaSqabeaacaaIYaaaaOGaaiikaiaadIhacaGGPaGaey4kaSIaci4yaiaac+gacaGGZbWaaWbaaSqabeaacaaIYaaaaOGaaiikaiaadIhacaGGPaGaeyypa0JaaGymaaaa@44C4@

podemos construir un par de funciones reales f y g tales que el punto (f(t),g(t)) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaiikaiaadAgacaGGOaGaamiDaiaacMcacaGGSaGaam4zaiaacIcacaWG0bGaaiykaiaacMcaaaa@3E71@   recorra la hipérbola

x 2 - y 2 =1 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaae4CaiaabwgacaqGUbWaaWbaaSqabeaacaaIYaaaaOGaaiikaiaadIhacaGGPaGaey4kaSIaci4yaiaac+gacaGGZbWaaWbaaSqabeaacaaIYaaaaOGaaiikaiaadIhacaGGPaGaeyypa0JaaGymaaaa@44C4@

Se trata de las funciones hiperbólicas seno y coseno; en símbolos, sinh(x) y cosh(x). Sin entrar en un análisis exhaustivo de tales funciones, exhibamos su manejo con Maple:

En primer lugar, Maple conoce su definición en términos de la función exponencial. En primer lugar, el seno hiperbólico se define mediante

> convert(sinh(x),exp);

1 2 e x 1 2 e ( x ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSaaaeaacaaIXaaabaGaaGOmaaaacaWGLbWaaWbaaSqabeaacaWG4baaaOGaeyOeI0YaaSaaaeaacaaIXaaabaGaaGOmaaaacaWGLbWaaWbaaSqabeaadaqadaqaaiabgkHiTiaadIhaaiaawIcacaGLPaaaaaaaaa@4090@

Asimismo, el coseno hiperbólico se define mediante

> convert(cosh(x),exp);

1 2 e x + 1 2 e ( x ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSaaaeaacaaIXaaabaGaaGOmaaaacaWGLbWaaWbaaSqabeaacaWG4baaaOGaeyOeI0YaaSaaaeaacaaIXaaabaGaaGOmaaaacaWGLbWaaWbaaSqabeaadaqadaqaaiabgkHiTiaadIhaaiaawIcacaGLPaaaaaaaaa@4090@

Estas funciones recorren la hipérbola

>simplify(cosh(x)^2-sinh(x)^2,trig);

1

Maple conoce que

tanh(x)= sinh(x) cosh(x)         csch(x)= 1 sinh(x)         sech(x)= 1 cosh(x)         coth(x)= 1 tanh(x)   MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiDaiaacggacaGGUbGaaiiAaiaacIcacaWG4bGaaiykaiabg2da9maalaaabaGaci4CaiaacMgacaGGUbGaaiiAaiaacIcacaWG4bGaaiykaaqaaiGacogacaGGVbGaai4CaiaacIgacaGGOaGaamiEaiaacMcaaaGaaeiiaiaabccacaqGGaGaaeiiaiaabccacaqGGaGaaeiiaiaabccaciGGJbGaai4CaiaacogacaGGObGaaiikaiaadIhacaGGPaGaeyypa0ZaaSaaaeaacaaIXaaabaGaci4CaiaacMgacaGGUbGaaiiAaiaacIcacaWG4bGaaiykaaaacaqGGaGaaeiiaiaabccacaqGGaGaaeiiaiaabccacaqGGaGaaeiiaiaabohacaqGLbGaae4yaiaabIgacaGGOaGaamiEaiaacMcacqGH9aqpdaWcaaqaaiaaigdaaeaaciGGJbGaai4BaiaacohacaGGObGaaiikaiaadIhacaGGPaaaaiaabccacaqGGaGaaeiiaiaabccacaqGGaGaaeiiaiaabccacaqGGaGaae4yaiaab+gacaqG0bGaaeiAaiaabIcacaWG4bGaaeykaiabg2da9maalaaabaGaaGymaaqaaiGacshacaGGHbGaaiOBaiaacIgacaGGOaGaamiEaiaacMcaaaGaaeiiaaaa@8301@

De hecho,

> simplify(tanh(x)-sinh(x)/cosh(x),trig);

0

> simplify(sinh(x)*csch(x),trig);

1

> simplify(cosh(x)*sech(x),trig);

1

> simplify(coth(x)*tanh(x),trig);

1

En consecuencia,

> convert(tanh(x),exp);

e x e ( x ) e x + e ( x ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSaaaeaacaWGLbWaaWbaaSqabeaacaWG4baaaOGaeyOeI0IaamyzamaaCaaaleqabaWaaeWaaeaacqGHsislcaWG4baacaGLOaGaayzkaaaaaaGcbaGaamyzamaaCaaaleqabaGaamiEaaaakiabgUcaRiaadwgadaahaaWcbeqaamaabmaabaGaeyOeI0IaamiEaaGaayjkaiaawMcaaaaaaaaaaa@4526@

> convert(coth(x),exp);

e x + e ( x ) e x e ( x ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSaaaeaacaWGLbWaaWbaaSqabeaacaWG4baaaOGaey4kaSIaamyzamaaCaaaleqabaWaaeWaaeaacqGHsislcaWG4baacaGLOaGaayzkaaaaaaGcbaGaamyzamaaCaaaleqabaGaamiEaaaakiabgkHiTiaadwgadaahaaWcbeqaamaabmaabaGaeyOeI0IaamiEaaGaayjkaiaawMcaaaaaaaaaaa@4526@

> convert(csch(x),exp);

2 e x e ( x ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSaaaeaacaaIYaaabaGaamyzamaaCaaaleqabaGaamiEaaaakiabgkHiTiaadwgadaahaaWcbeqaamaabmaabaGaeyOeI0IaamiEaaGaayjkaiaawMcaaaaaaaaaaa@3E4E@

> convert(sech(x),exp);

2 e x + e ( x ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaSaaaeaacaaIYaaabaGaamyzamaaCaaaleqabaGaamiEaaaakiabgkHiTiaadwgadaahaaWcbeqaamaabmaabaGaeyOeI0IaamiEaaGaayjkaiaawMcaaaaaaaaaaa@3E4E@

Por tanto, derivación e integración simbólica y numérica no son ya un secreto para Maple

> diff(sinh(x),x);

cosh(x)

> int(sinh(x),x);

cosh(x)

> int(cosh(x),x=0..1.); Nótese el "." que sigue al 1, indicando cálculo en coma flotante

1.175201194