Bất phương trình \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaaiaaikdaaeqaaOWaaeWaaeaacaWG4bWaaWba % aSqabeaacaaIYaaaaOGaeyOeI0IaaGOmaiaadIhacqGHRaWkcaaIZa % aacaGLOaGaayzkaaGaeyOpa4JaaGymaaaa!4337! {\log _2}\left( {{x^2} - 2x + 3} \right) > 1\) có tập nghiệm là
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+-
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{\log _2}\left( {{x^2} - 2x + 3} \right) > 1 \Leftrightarrow {x^2} - 2x + 3 > {2^1} \Leftrightarrow {x^2} - 2x + 1 > 0 \Leftrightarrow {\left( {x - 1} \right)^2} > 0 \Leftrightarrow x \ne 1\)
Vậy tập nghiệm S = R\{1}