Với a, b là các số thực dương bất kì, \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaaiaaikdaaeqaaOWaaSaaaeaacaWGHbaabaGa % amOyamaaCaaaleqabaGaaGOmaaaaaaaaaa!3C7C! {\log _2}\frac{a}{{{b^2}}}\) bằng:
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Lời giải:
Báo saiTa có: \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaciiBaiaac+ % gacaGGNbWaaSbaaSqaaiaaikdaaeqaaOWaaSaaaeaacaWGHbaabaGa % amOyamaaCaaaleqabaGaaGOmaaaaaaGccqGH9aqpciGGSbGaai4Bai % aacEgadaWgaaWcbaGaaGOmaaqabaGccaWGHbGaeyOeI0IaciiBaiaa % c+gacaGGNbWaaSbaaSqaaiaaikdaaeqaaOGaamOyamaaCaaaleqaba % GaaGOmaaaakiabg2da9iGacYgacaGGVbGaai4zamaaBaaaleaacaaI % YaaabeaakiaadggacqGHsislcaaIYaGaciiBaiaac+gacaGGNbWaaS % baaSqaaiaaikdaaeqaaOGaamOyaaaa!54BD! {\log _2}\frac{a}{{{b^2}}} = {\log _2}a - {\log _2}{b^2} = {\log _2}a - 2{\log _2}b\)
Đề thi thử tốt nghiệp THPT QG môn Toán năm 2020
Tuyển chọn số 4