Tìm tất cả các giá trị thực của tham số m để bất phương trình \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaaiaaikdaaeqaaOGaaiikaiaaiwdadaahaaWc % beqaaiaadIhaaaGccqGHsislcaaIXaGaaiykaiabgsMiJkaad2gaaa % a!4151! {\log _2}({5^x} - 1) \le m\) có nghiệm \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiEaiabgw % MiZkaaigdaaaa!3972! x \ge 1\) ?
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiEaiabgw % MiZkaaigdacqGHuhY2caaI1aWaaWbaaSqabeaacaWG4baaaOGaeyOe % I0IaaGymaiabgwMiZkaaisdacqGHuhY2ciGGSbGaai4BaiaacEgada % WgaaWcbaGaaGOmaaqabaGcdaqadaqaaiaaiwdadaahaaWcbeqaaiaa % dIhaaaGccqGHsislcaaIXaaacaGLOaGaayzkaaGaeyyzImRaaGOmai % abgsDiBlaad2gacqGHLjYScaaIYaaaaa!5581! x \ge 1 \Leftrightarrow {5^x} - 1 \ge 4 \Leftrightarrow {\log _2}\left( {{5^x} - 1} \right) \ge 2 \Leftrightarrow m \ge 2\)