Se da la desigualdad:
( x 2 − 16 ) log ( 3 ) 2 − 5 log ( x 2 − 16 ) log ( 3 ) ≥ 0 \left(x^{2} - 16\right) \log{\left(3 \right)}^{2} - 5 \frac{\log{\left(x^{2} - 16 \right)}}{\log{\left(3 \right)}} \geq 0 ( x 2 − 16 ) log ( 3 ) 2 − 5 log ( 3 ) log ( x 2 − 16 ) ≥ 0 Para resolver esta desigualdad primero hay que resolver la ecuación correspondiente:
( x 2 − 16 ) log ( 3 ) 2 − 5 log ( x 2 − 16 ) log ( 3 ) = 0 \left(x^{2} - 16\right) \log{\left(3 \right)}^{2} - 5 \frac{\log{\left(x^{2} - 16 \right)}}{\log{\left(3 \right)}} = 0 ( x 2 − 16 ) log ( 3 ) 2 − 5 log ( 3 ) log ( x 2 − 16 ) = 0 Resolvemos:
x 1 = − − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{1} = - \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 1 = − log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 2 = − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{2} = \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 2 = log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 3 = − − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{3} = - \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 3 = − log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 4 = − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{4} = \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 4 = log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 1 = − − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{1} = - \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 1 = − log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 2 = − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{2} = \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 2 = log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 3 = − − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{3} = - \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 3 = − log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 4 = − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{4} = \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 4 = log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 Las raíces dadas
x 3 = − − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{3} = - \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 3 = − log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 1 = − − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{1} = - \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 1 = − log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 2 = − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{2} = \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 2 = log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x 4 = − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x_{4} = \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x 4 = log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 son puntos de cambio del signo de desigualdad en las soluciones.
Primero definámonos con el signo hasta el punto extremo izquierdo:
x 0 ≤ x 3 x_{0} \leq x_{3} x 0 ≤ x 3 Consideremos, por ejemplo, el punto
x 0 = x 3 − 1 10 x_{0} = x_{3} - \frac{1}{10} x 0 = x 3 − 10 1 =
− − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 + − 1 10 - \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} + - \frac{1}{10} − log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 + − 10 1 =
− − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 − 1 10 - \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} - \frac{1}{10} − log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 − 10 1 lo sustituimos en la expresión
( x 2 − 16 ) log ( 3 ) 2 − 5 log ( x 2 − 16 ) log ( 3 ) ≥ 0 \left(x^{2} - 16\right) \log{\left(3 \right)}^{2} - 5 \frac{\log{\left(x^{2} - 16 \right)}}{\log{\left(3 \right)}} \geq 0 ( x 2 − 16 ) log ( 3 ) 2 − 5 log ( 3 ) log ( x 2 − 16 ) ≥ 0 / 2 \
|/ ___________________________________\ |
|| / / 3 \ | |
/ 2 \ || / |-log (3) | 3 | |
|/ ___________________________________\ | || / - 5*W|---------, -1| + 16*log (3) | |
|| / / 3 \ | | || 1 \/ \ 5 / | |
|| / |-log (3) | 3 | | log||- -- - ----------------------------------------| - 16|
|| / - 5*W|---------, -1| + 16*log (3) | | || 10 3/2 | |
2 || 1 \/ \ 5 / | | \\ log (3) / /
log (3)*||- -- - ----------------------------------------| - 16| - 5*------------------------------------------------------------ >= 0
|| 10 3/2 | | 1
\\ log (3) / / log (3) / 2\
| / ___________________________________\ |
| | / / 3 \ | |
/ 2\ | | / |-log (3) | 3 | |
| / ___________________________________\ | | | / - 5*W|---------, -1| + 16*log (3) | |
| | / / 3 \ | | | | 1 \/ \ 5 / | |
| | / |-log (3) | 3 | | 5*log|-16 + |- -- - ----------------------------------------| | >= 0
| | / - 5*W|---------, -1| + 16*log (3) | | | | 10 3/2 | |
2 | | 1 \/ \ 5 / | | \ \ log (3) / /
log (3)*|-16 + |- -- - ----------------------------------------| | - ---------------------------------------------------------------
| | 10 3/2 | | log(3)
\ \ log (3) / /
significa que una de las soluciones de nuestra ecuación será con:
x ≤ − − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x \leq - \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x ≤ − log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 _____ _____ _____
\ / \ /
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x3 x1 x2 x4 Recibiremos otras soluciones de la desigualdad pasando al polo siguiente etc.
etc.
Respuesta:
x ≤ − − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x \leq - \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x ≤ − log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x ≥ − − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 ∧ x ≤ − 5 W ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x \geq - \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} \wedge x \leq \frac{\sqrt{- 5 W\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x ≥ − log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 ∧ x ≤ log ( 3 ) 2 3 − 5 W ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3 x ≥ − 5 W − 1 ( − log ( 3 ) 3 5 ) + 16 log ( 3 ) 3 log ( 3 ) 3 2 x \geq \frac{\sqrt{- 5 W_{-1}\left(- \frac{\log{\left(3 \right)}^{3}}{5}\right) + 16 \log{\left(3 \right)}^{3}}}{\log{\left(3 \right)}^{\frac{3}{2}}} x ≥ log ( 3 ) 2 3 − 5 W − 1 ( − 5 l o g ( 3 ) 3 ) + 16 log ( 3 ) 3