Tìm số nghiệm nguyên của bất phương trình \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaamaakaaabaGaaG4maaadbeaaliabgkHiTiaa % igdaaeqaaOWaaeWaaeaacaWG4bWaaWbaaSqabeaacaaIYaaaaOGaey % OeI0IaaGOmaiaadIhacqGHRaWkcaaIXaaacaGLOaGaayzkaaGaeyOp % a4JaaGimaiaac6caaaa!45B6! {\log _{\sqrt 3 - 1}}\left( {{x^2} - 2x + 1} \right) > 0.\)
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Lời giải:
Báo saiĐiều kiện: \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiEamaaCa % aaleqabaGaaGOmaaaakiabgkHiTiaaikdacaWG4bGaey4kaSIaaGym % aiabg6da+iaaicdacqGHuhY2daqadaqaaiaadIhacqGHsislcaaIXa % aacaGLOaGaayzkaaWaaWbaaSqabeaacaaIYaaaaOGaeyOpa4JaaGim % aiabgsDiBlaadIhacqGHGjsUcaaIXaaaaa!4D03! {x^2} - 2x + 1 > 0 \Leftrightarrow {\left( {x - 1} \right)^2} > 0 \Leftrightarrow x \ne 1\)
\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaamaakaaabaGaaG4maaadbeaaliabgkHiTiaa % igdaaeqaaOWaaeWaaeaacaWG4bWaaWbaaSqabeaacaaIYaaaaOGaey % OeI0IaaGOmaiaadIhacqGHRaWkcaaIXaaacaGLOaGaayzkaaGaeyOp % a4JaaGimaiabgsDiBlGacYgacaGGVbGaai4zamaaBaaaleaadaGcaa % qaaiaaiodaaWqabaWccqGHsislcaaIXaaabeaakmaabmaabaGaamiE % amaaCaaaleqabaGaaGOmaaaakiabgkHiTiaaikdacaWG4bGaey4kaS % IaaGymaaGaayjkaiaawMcaaiabg6da+iGacYgacaGGVbGaai4zamaa % BaaaleaadaGcaaqaaiaaiodaaWqabaWccqGHsislcaaIXaaabeaaki % aaigdacqGHuhY2caWG4bWaaWbaaSqabeaacaaIYaaaaOGaeyOeI0Ia % aGOmaiaadIhacqGHRaWkcaaIXaGaeyipaWJaaGymaaaa!6651! {\log _{\sqrt 3 - 1}}\left( {{x^2} - 2x + 1} \right) > 0 \Leftrightarrow {\log _{\sqrt 3 - 1}}\left( {{x^2} - 2x + 1} \right) > {\log _{\sqrt 3 - 1}}1 \Leftrightarrow {x^2} - 2x + 1 < 1\)
\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiEamaaCa % aaleqabaGaaGOmaaaakiabgkHiTiaaikdacaWG4bGaeyipaWJaaGim % aiabgsDiBlaaicdacqGH8aapcaWG4bGaeyipaWJaaGOmaaaa!431F! {x^2} - 2x < 0 \Leftrightarrow 0 < x < 2\)
Vì x nguyên, \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiEaiabgc % Mi5kaaigdacqGHshI3caWG4bGaeyicI4SaeyybIymaaa!3FCA! x \ne 1 \Rightarrow x \in \emptyset \)