Điều kiện xác định của bất phương trình \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaaiaaicdacaGGSaGaaGynaaqabaGccaGGOaGa % aGynaiaabIhacqGHRaWkcaaIXaGaaGynaiaacMcacqGHKjYOciGGSb % Gaai4BaiaacEgadaWgaaWcbaGaaGimaiaacYcacaaI1aaabeaakmaa % bmaabaGaamiEamaaCaaaleqabaGaaGOmaaaakiabgUcaRiaaiAdaca % qG4bGaey4kaSIaaGioaaGaayjkaiaawMcaaaaa!4F30! {\log _{0,5}}(5{\rm{x}} + 15) \le {\log _{0,5}}\left( {{x^2} + 6{\rm{x}} + 8} \right)\) là:
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Lời giải:
Báo saiĐiều kiện \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaiqaaqaabe % qaaiaaiwdacaWG4bGaey4kaSIaaGymaiaaiwdacqGH+aGpcaaIWaaa % baGaamiEamaaCaaaleqabaGaaGOmaaaakiabgUcaRiaaiAdacaqG4b % Gaey4kaSIaaGioaiabg6da+iaaicdaaaGaay5EaaGaeyi1HS9aaiqa % aqaabeqaaiaadIhacqGH+aGpcqGHsislcaaIZaaabaWaamqaaqaabe % qaaiaadIhacqGH+aGpcqGHsislcaaIYaaabaGaamiEaiabgYda8iab % gkHiTiaaisdaaaGaay5waaaaaiaawUhaaiabgsDiBlaadIhacqGH+a % GpcqGHsislcaaIYaaaaa!5A74! \left\{ \begin{array}{l} 5x + 15 > 0\\ {x^2} + 6{\rm{x}} + 8 > 0 \end{array} \right. \Leftrightarrow \left\{ \begin{array}{l} x > - 3\\ \left[ \begin{array}{l} x > - 2\\ x < - 4 \end{array} \right. \end{array} \right. \Leftrightarrow x > - 2\)