Bất phương trình \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaamaalaaabaGaaGymaaqaaiaaikdaaaaabeaa % kmaabmaabaGaciiBaiaac+gacaGGNbWaaSbaaSqaaiaaiodaaeqaaO % WaaSaaaeaacaaIYaGaamiEaiabgUcaRiaaigdaaeaacaWG4bGaeyOe % I0IaaGymaaaaaiaawIcacaGLPaaacqGH+aGpcaaIWaaaaa!479A! {\log _{\frac{1}{2}}}\left( {{{\log }_3}\frac{{2x + 1}}{{x - 1}}} \right) > 0\) có tập nghiệm là
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaamaalaaabaGaaGymaaqaaiaaikdaaaaabeaa % kmaabmaabaGaciiBaiaac+gacaGGNbWaaSbaaSqaaiaaiodaaeqaaO % WaaSaaaeaacaaIYaGaamiEaiabgUcaRiaaigdaaeaacaWG4bGaeyOe % I0IaaGymaaaaaiaawIcacaGLPaaacqGH+aGpcaaIWaGaeyi1HS9aai % qaaqaabeqaaiGacYgacaGGVbGaai4zamaaBaaaleaacaaIZaaabeaa % kmaalaaabaGaaGOmaiaadIhacqGHRaWkcaaIXaaabaGaamiEaiabgk % HiTiaaigdaaaGaeyOpa4JaaGimaaqaaiGacYgacaGGVbGaai4zamaa % BaaaleaacaaIZaaabeaakmaalaaabaGaaGOmaiaadIhacqGHRaWkca % aIXaaabaGaamiEaiabgkHiTiaaigdaaaGaeyipaWJaaGymaaaacaGL % 7baacqGHuhY2daGabaabaeqabaWaaSaaaeaacaaIYaGaamiEaiabgU % caRiaaigdaaeaacaWG4bGaeyOeI0IaaGymaaaacqGH+aGpcaaIXaaa % baWaaSaaaeaacaaIYaGaamiEaiabgUcaRiaaigdaaeaacaWG4bGaey % OeI0IaaGymaaaacqGH8aapcaaIZaaaaiaawUhaaiabgsDiBpaaceaa % eaqabeaadaWcaaqaaiaadIhacqGHRaWkcaaIYaaabaGaamiEaiabgk % HiTiaaigdaaaGaeyOpa4JaaGimaaqaamaalaaabaGaeyOeI0IaamiE % aiabgUcaRiaaisdaaeaacaWG4bGaeyOeI0IaaGymaaaacqGH8aapca % aIWaaaaiaawUhaaiabgsDiBpaadeaaeaqabeaacaWG4bGaeyipaWJa % eyOeI0IaaGOmaaqaaiaadIhacqGH+aGpcaaI0aaaaiaawUfaaaaa!91A2! {\log _{\frac{1}{2}}}\left( {{{\log }_3}\frac{{2x + 1}}{{x - 1}}} \right) > 0 \Leftrightarrow \left\{ \begin{array}{l} {\log _3}\frac{{2x + 1}}{{x - 1}} > 0\\ {\log _3}\frac{{2x + 1}}{{x - 1}} < 1 \end{array} \right. \Leftrightarrow \left\{ \begin{array}{l} \frac{{2x + 1}}{{x - 1}} > 1\\ \frac{{2x + 1}}{{x - 1}} < 3 \end{array} \right. \Leftrightarrow \left\{ \begin{array}{l} \frac{{x + 2}}{{x - 1}} > 0\\ \frac{{ - x + 4}}{{x - 1}} < 0 \end{array} \right. \Leftrightarrow \left[ \begin{array}{l} x < - 2\\ x > 4 \end{array} \right.\)