Tính tích các nghiệm thực của phương trình \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaGOmamaaCa % aaleqabaGaamiEamaaCaaameqabaGaaGOmaaaaliabgkHiTiaaigda % aaGccqGH9aqpcaaIZaWaaWbaaSqabeaacaaIYaGaamiEaiabgUcaRi % aaiodaaaaaaa!3FC8! {2^{{x^2} - 1}} = {3^{2x + 3}}\).
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Lời giải:
Báo saiTa có \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaGOmamaaCa % aaleqabaGaamiEamaaCaaameqabaGaaGOmaaaaliabgkHiTiaaigda % aaGccqGH9aqpcaaIZaWaaWbaaSqabeaacaaIYaGaamiEaiabgUcaRi % aaiodaaaGccqGHuhY2caWG4bWaaWbaaSqabeaacaaIYaaaaOGaeyOe % I0IaaGymaiabg2da9maabmaabaGaaGOmaiaadIhacqGHRaWkcaaIZa % aacaGLOaGaayzkaaGaciiBaiaac+gacaGGNbWaaSbaaSqaaiaaikda % aeqaaOGaaG4maiabgsDiBlaadIhadaahaaWcbeqaaiaaikdaaaGccq % GHsislcaaIYaGaamiEaiGacYgacaGGVbGaai4zamaaBaaaleaacaaI % YaaabeaakiaaiodacqGHsislcaaIZaGaciiBaiaac+gacaGGNbWaaS % baaSqaaiaaikdaaeqaaOGaaG4maiabgkHiTiaaigdacqGH9aqpcaaI % Waaaaa!652E! {2^{{x^2} - 1}} = {3^{2x + 3}} \Leftrightarrow {x^2} - 1 = \left( {2x + 3} \right){\log _2}3 \Leftrightarrow {x^2} - 2x{\log _2}3 - 3{\log _2}3 - 1 = 0\)
\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiEamaaBa % aaleaacaaIXaaabeaakiaac6cacaWG4bWaaSbaaSqaaiaaikdaaeqa % aOGaeyypa0JaeyOeI0IaaG4maiGacYgacaGGVbGaai4zamaaBaaale % aacaaIYaaabeaakiaaiodacqGHsislcaaIXaGaeyypa0JaeyOeI0Ia % ciiBaiaac+gacaGGNbWaaSbaaSqaaiaaikdaaeqaaOGaaGynaiaais % daaaa!4A8B! {x_1}.{x_2} = - 3{\log _2}3 - 1 = - {\log _2}54\)
Đề thi thử tốt nghiệp THPT QG môn Toán năm 2020
Tuyển chọn số 5