Sr Examen

cost<1/3 desigualdades

En la desigualdad la incógnita

Solución

Ha introducido [src]
cos(t) < 1/3
$$\cos{\left(t \right)} < \frac{1}{3}$$
cos(t) < 1/3
Solución detallada
Se da la desigualdad:
$$\cos{\left(t \right)} < \frac{1}{3}$$
Para resolver esta desigualdad primero hay que resolver la ecuación correspondiente:
$$\cos{\left(t \right)} = \frac{1}{3}$$
Resolvemos:
Tenemos la ecuación
$$\cos{\left(t \right)} = \frac{1}{3}$$
cambiamos
$$\cos{\left(t \right)} - \frac{1}{3} = 0$$
$$\cos{\left(t \right)} - \frac{1}{3} = 0$$
Sustituimos
$$w = \cos{\left(t \right)}$$
Transportamos los términos libres (sin w)
del miembro izquierdo al derecho, obtenemos:
$$w = \frac{1}{3}$$
Obtenemos la respuesta: w = 1/3
hacemos cambio inverso
$$\cos{\left(t \right)} = w$$
sustituimos w:
$$x_{1} = -55.3177083472755$$
$$x_{2} = -38.9300712604183$$
$$x_{3} = 93.016820190353$$
$$x_{4} = -32.6468859532387$$
$$x_{5} = 70.3459977963162$$
$$x_{6} = -99.3000054975326$$
$$x_{7} = -64.0628124891366$$
$$x_{8} = 82.9123684106754$$
$$x_{9} = -42.7513377329163$$
$$x_{10} = -67.8840789616347$$
$$x_{11} = 13.7973300316999$$
$$x_{12} = 7.51414472452036$$
$$x_{13} = 80.4504495759938$$
$$x_{14} = -45.2132565675979$$
$$x_{15} = -61.6008936544551$$
$$x_{16} = -30.1849671185572$$
$$x_{17} = 45.2132565675979$$
$$x_{18} = -1.23095941734077$$
$$x_{19} = 11.3354111970184$$
$$x_{20} = 89.195553717855$$
$$x_{21} = -7.51414472452036$$
$$x_{22} = 20.0805153388795$$
$$x_{23} = -36.4681524257367$$
$$x_{24} = -57.7796271819571$$
$$x_{25} = 86.7336348831734$$
$$x_{26} = 67.8840789616347$$
$$x_{27} = -11.3354111970184$$
$$x_{28} = 30.1849671185572$$
$$x_{29} = 42.7513377329163$$
$$x_{30} = -95.4787390250346$$
$$x_{31} = 57.7796271819571$$
$$x_{32} = -5.05222588983881$$
$$x_{33} = -20.0805153388795$$
$$x_{34} = 17.618596504198$$
$$x_{35} = 74.1672642688143$$
$$x_{36} = 95.4787390250346$$
$$x_{37} = 1.23095941734077$$
$$x_{38} = 55.3177083472755$$
$$x_{39} = 61.6008936544551$$
$$x_{40} = -80.4504495759938$$
$$x_{41} = 51.4964418747775$$
$$x_{42} = 23.9017818113776$$
$$x_{43} = -89.195553717855$$
$$x_{44} = 32.6468859532387$$
$$x_{45} = -23.9017818113776$$
$$x_{46} = 76.6291831034958$$
$$x_{47} = -325.494676555998$$
$$x_{48} = -86.7336348831734$$
$$x_{49} = -26.3637006460591$$
$$x_{50} = 38.9300712604183$$
$$x_{51} = -51.4964418747775$$
$$x_{52} = 26.3637006460591$$
$$x_{53} = -82.9123684106754$$
$$x_{54} = -70.3459977963162$$
$$x_{55} = -76.6291831034958$$
$$x_{56} = 36.4681524257367$$
$$x_{57} = 5.05222588983881$$
$$x_{58} = 99.3000054975326$$
$$x_{59} = 64.0628124891366$$
$$x_{60} = -101.761924332214$$
$$x_{61} = -17.618596504198$$
$$x_{62} = -49.0345230400959$$
$$x_{63} = -93.016820190353$$
$$x_{64} = 49.0345230400959$$
$$x_{65} = -74.1672642688143$$
$$x_{66} = -13.7973300316999$$
$$x_{1} = -55.3177083472755$$
$$x_{2} = -38.9300712604183$$
$$x_{3} = 93.016820190353$$
$$x_{4} = -32.6468859532387$$
$$x_{5} = 70.3459977963162$$
$$x_{6} = -99.3000054975326$$
$$x_{7} = -64.0628124891366$$
$$x_{8} = 82.9123684106754$$
$$x_{9} = -42.7513377329163$$
$$x_{10} = -67.8840789616347$$
$$x_{11} = 13.7973300316999$$
$$x_{12} = 7.51414472452036$$
$$x_{13} = 80.4504495759938$$
$$x_{14} = -45.2132565675979$$
$$x_{15} = -61.6008936544551$$
$$x_{16} = -30.1849671185572$$
$$x_{17} = 45.2132565675979$$
$$x_{18} = -1.23095941734077$$
$$x_{19} = 11.3354111970184$$
$$x_{20} = 89.195553717855$$
$$x_{21} = -7.51414472452036$$
$$x_{22} = 20.0805153388795$$
$$x_{23} = -36.4681524257367$$
$$x_{24} = -57.7796271819571$$
$$x_{25} = 86.7336348831734$$
$$x_{26} = 67.8840789616347$$
$$x_{27} = -11.3354111970184$$
$$x_{28} = 30.1849671185572$$
$$x_{29} = 42.7513377329163$$
$$x_{30} = -95.4787390250346$$
$$x_{31} = 57.7796271819571$$
$$x_{32} = -5.05222588983881$$
$$x_{33} = -20.0805153388795$$
$$x_{34} = 17.618596504198$$
$$x_{35} = 74.1672642688143$$
$$x_{36} = 95.4787390250346$$
$$x_{37} = 1.23095941734077$$
$$x_{38} = 55.3177083472755$$
$$x_{39} = 61.6008936544551$$
$$x_{40} = -80.4504495759938$$
$$x_{41} = 51.4964418747775$$
$$x_{42} = 23.9017818113776$$
$$x_{43} = -89.195553717855$$
$$x_{44} = 32.6468859532387$$
$$x_{45} = -23.9017818113776$$
$$x_{46} = 76.6291831034958$$
$$x_{47} = -325.494676555998$$
$$x_{48} = -86.7336348831734$$
$$x_{49} = -26.3637006460591$$
$$x_{50} = 38.9300712604183$$
$$x_{51} = -51.4964418747775$$
$$x_{52} = 26.3637006460591$$
$$x_{53} = -82.9123684106754$$
$$x_{54} = -70.3459977963162$$
$$x_{55} = -76.6291831034958$$
$$x_{56} = 36.4681524257367$$
$$x_{57} = 5.05222588983881$$
$$x_{58} = 99.3000054975326$$
$$x_{59} = 64.0628124891366$$
$$x_{60} = -101.761924332214$$
$$x_{61} = -17.618596504198$$
$$x_{62} = -49.0345230400959$$
$$x_{63} = -93.016820190353$$
$$x_{64} = 49.0345230400959$$
$$x_{65} = -74.1672642688143$$
$$x_{66} = -13.7973300316999$$
Las raíces dadas
$$x_{47} = -325.494676555998$$
$$x_{60} = -101.761924332214$$
$$x_{6} = -99.3000054975326$$
$$x_{30} = -95.4787390250346$$
$$x_{63} = -93.016820190353$$
$$x_{43} = -89.195553717855$$
$$x_{48} = -86.7336348831734$$
$$x_{53} = -82.9123684106754$$
$$x_{40} = -80.4504495759938$$
$$x_{55} = -76.6291831034958$$
$$x_{65} = -74.1672642688143$$
$$x_{54} = -70.3459977963162$$
$$x_{10} = -67.8840789616347$$
$$x_{7} = -64.0628124891366$$
$$x_{15} = -61.6008936544551$$
$$x_{24} = -57.7796271819571$$
$$x_{1} = -55.3177083472755$$
$$x_{51} = -51.4964418747775$$
$$x_{62} = -49.0345230400959$$
$$x_{14} = -45.2132565675979$$
$$x_{9} = -42.7513377329163$$
$$x_{2} = -38.9300712604183$$
$$x_{23} = -36.4681524257367$$
$$x_{4} = -32.6468859532387$$
$$x_{16} = -30.1849671185572$$
$$x_{49} = -26.3637006460591$$
$$x_{45} = -23.9017818113776$$
$$x_{33} = -20.0805153388795$$
$$x_{61} = -17.618596504198$$
$$x_{66} = -13.7973300316999$$
$$x_{27} = -11.3354111970184$$
$$x_{21} = -7.51414472452036$$
$$x_{32} = -5.05222588983881$$
$$x_{18} = -1.23095941734077$$
$$x_{37} = 1.23095941734077$$
$$x_{57} = 5.05222588983881$$
$$x_{12} = 7.51414472452036$$
$$x_{19} = 11.3354111970184$$
$$x_{11} = 13.7973300316999$$
$$x_{34} = 17.618596504198$$
$$x_{22} = 20.0805153388795$$
$$x_{42} = 23.9017818113776$$
$$x_{52} = 26.3637006460591$$
$$x_{28} = 30.1849671185572$$
$$x_{44} = 32.6468859532387$$
$$x_{56} = 36.4681524257367$$
$$x_{50} = 38.9300712604183$$
$$x_{29} = 42.7513377329163$$
$$x_{17} = 45.2132565675979$$
$$x_{64} = 49.0345230400959$$
$$x_{41} = 51.4964418747775$$
$$x_{38} = 55.3177083472755$$
$$x_{31} = 57.7796271819571$$
$$x_{39} = 61.6008936544551$$
$$x_{59} = 64.0628124891366$$
$$x_{26} = 67.8840789616347$$
$$x_{5} = 70.3459977963162$$
$$x_{35} = 74.1672642688143$$
$$x_{46} = 76.6291831034958$$
$$x_{13} = 80.4504495759938$$
$$x_{8} = 82.9123684106754$$
$$x_{25} = 86.7336348831734$$
$$x_{20} = 89.195553717855$$
$$x_{3} = 93.016820190353$$
$$x_{36} = 95.4787390250346$$
$$x_{58} = 99.3000054975326$$
son puntos de cambio del signo de desigualdad en las soluciones.
Primero definámonos con el signo hasta el punto extremo izquierdo:
$$x_{0} < x_{47}$$
Consideremos, por ejemplo, el punto
$$x_{0} = x_{47} - \frac{1}{10}$$
=
$$-325.494676555998 + - \frac{1}{10}$$
=
$$-325.594676555998$$
lo sustituimos en la expresión
$$\cos{\left(t \right)} < \frac{1}{3}$$
$$\cos{\left(t \right)} < \frac{1}{3}$$
cos(t) < 1/3

Entonces
$$x < -325.494676555998$$
no se cumple
significa que una de las soluciones de nuestra ecuación será con:
$$x > -325.494676555998 \wedge x < -101.761924332214$$
         _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____  
        /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \  
-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------
       x47      x60      x6      x30      x63      x43      x48      x53      x40      x55      x65      x54      x10      x7      x15      x24      x1      x51      x62      x14      x9      x2      x23      x4      x16      x49      x45      x33      x61      x66      x27      x21      x32      x18      x37      x57      x12      x19      x11      x34      x22      x42      x52      x28      x44      x56      x50      x29      x17      x64      x41      x38      x31      x39      x59      x26      x5      x35      x46      x13      x8      x25      x20      x3      x36      x58

Recibiremos otras soluciones de la desigualdad pasando al polo siguiente etc.
etc.
Respuesta:
$$x > -325.494676555998 \wedge x < -101.761924332214$$
$$x > -99.3000054975326 \wedge x < -95.4787390250346$$
$$x > -93.016820190353 \wedge x < -89.195553717855$$
$$x > -86.7336348831734 \wedge x < -82.9123684106754$$
$$x > -80.4504495759938 \wedge x < -76.6291831034958$$
$$x > -74.1672642688143 \wedge x < -70.3459977963162$$
$$x > -67.8840789616347 \wedge x < -64.0628124891366$$
$$x > -61.6008936544551 \wedge x < -57.7796271819571$$
$$x > -55.3177083472755 \wedge x < -51.4964418747775$$
$$x > -49.0345230400959 \wedge x < -45.2132565675979$$
$$x > -42.7513377329163 \wedge x < -38.9300712604183$$
$$x > -36.4681524257367 \wedge x < -32.6468859532387$$
$$x > -30.1849671185572 \wedge x < -26.3637006460591$$
$$x > -23.9017818113776 \wedge x < -20.0805153388795$$
$$x > -17.618596504198 \wedge x < -13.7973300316999$$
$$x > -11.3354111970184 \wedge x < -7.51414472452036$$
$$x > -5.05222588983881 \wedge x < -1.23095941734077$$
$$x > 1.23095941734077 \wedge x < 5.05222588983881$$
$$x > 7.51414472452036 \wedge x < 11.3354111970184$$
$$x > 13.7973300316999 \wedge x < 17.618596504198$$
$$x > 20.0805153388795 \wedge x < 23.9017818113776$$
$$x > 26.3637006460591 \wedge x < 30.1849671185572$$
$$x > 32.6468859532387 \wedge x < 36.4681524257367$$
$$x > 38.9300712604183 \wedge x < 42.7513377329163$$
$$x > 45.2132565675979 \wedge x < 49.0345230400959$$
$$x > 51.4964418747775 \wedge x < 55.3177083472755$$
$$x > 57.7796271819571 \wedge x < 61.6008936544551$$
$$x > 64.0628124891366 \wedge x < 67.8840789616347$$
$$x > 70.3459977963162 \wedge x < 74.1672642688143$$
$$x > 76.6291831034958 \wedge x < 80.4504495759938$$
$$x > 82.9123684106754 \wedge x < 86.7336348831734$$
$$x > 89.195553717855 \wedge x < 93.016820190353$$
$$x > 95.4787390250346 \wedge x < 99.3000054975326$$
Respuesta rápida [src]
   /          /    ___\             /    ___\    \
And\t < - atan\2*\/ 2 / + 2*pi, atan\2*\/ 2 / < t/
$$t < - \operatorname{atan}{\left(2 \sqrt{2} \right)} + 2 \pi \wedge \operatorname{atan}{\left(2 \sqrt{2} \right)} < t$$
(atan(2*sqrt(2)) < t)∧(t < -atan(2*sqrt(2)) + 2*pi)
Respuesta rápida 2 [src]
     /    ___\        /    ___\        
(atan\2*\/ 2 /, - atan\2*\/ 2 / + 2*pi)
$$x\ in\ \left(\operatorname{atan}{\left(2 \sqrt{2} \right)}, - \operatorname{atan}{\left(2 \sqrt{2} \right)} + 2 \pi\right)$$
x in Interval.open(atan(2*sqrt(2)), -atan(2*sqrt(2)) + 2*pi)