Giả sử \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGacaGaaiaabeqaamaabaabaaGcbaWaa8qCaeaada % WcaaqaaiaaigdaaeaacaaIYaGaamiEaiabgUcaRiaaigdaaaGaaeiz % aiaadIhaaSqaaiaaigdaaeaacaaIYaaaniabgUIiYdGccqGH9aqpci % GGSbGaaiOBamaakaaabaWaaSaaaeaacaWGHbaabaGaamOyaaaaaSqa % baaaaa!44C3! \int\limits_1^2 {\frac{1}{{2x + 1}}{\rm{d}}x} = \ln \sqrt {\frac{a}{b}} \) với \(a,b \in N^*\) và a,b < 10 . TÍnh \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGacaGaaiaabeqaamaabaabaaGcbaGaamytaiabg2 % da9iaadggacqGHRaWkcaWGIbWaaWbaaSqabeaacaaIYaaaaaaa!3B62! M = a + {b^2}\)
Suy nghĩ và trả lời câu hỏi trước khi xem đáp án
Lời giải:
Báo saiTa có \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGacaGaaiaabeqaamaabaabaaGcbaWaa8qCaeaada % WcaaqaaiaaigdaaeaacaaIYaGaamiEaiabgUcaRiaaigdaaaGaaeiz % aiaadIhaaSqaaiaaigdaaeaacaaIYaaaniabgUIiYdaaaa!3FD7! \int\limits_1^2 {\frac{1}{{2x + 1}}{\rm{d}}x} \)\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGacaGaaiaabeqaamaabaabaaGcbaGaeyypa0Zaaq % GaaeaadaqadaqaamaalaaabaGaaGymaaqaaiaaikdaaaGaciiBaiaa % c6gadaabdaqaaiaaikdacaWG4bGaey4kaSIaaGymaaGaay5bSlaawI % a7aaGaayjkaiaawMcaaaGaayjcSdWaa0baaSqaaiaaigdaaeaacaaI % Yaaaaaaa!459D! = \left. {\left( {\frac{1}{2}\ln \left| {2x + 1} \right|} \right)} \right|_1^2\)\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGacaGaaiaabeqaamaabaabaaGcbaGaeyypa0ZaaS % aaaeaacaaIXaaabaGaaGOmaaaaciGGSbGaaiOBamaalaaabaGaaGyn % aaqaaiaaiodaaaaaaa!3BEF! = \frac{1}{2}\ln \frac{5}{3}\)\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGacaGaaiaabeqaamaabaabaaGcbaGaeyypa0Jaci % iBaiaac6gadaGcaaqaamaalaaabaGaaGynaaqaaiaaiodaaaaaleqa % aaaa!3A83! = \ln \sqrt {\frac{5}{3}} \)
a = 5, b = 3 \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGacaGaaiaabeqaamaabaabaaGcbaGaeyO0H4Taam % ytaiabg2da9iaaiwdacqGHRaWkcaaIZaWaaWbaaSqabeaacaaIYaaa % aOGaeyypa0JaaGymaiaaisdaaaa!3FF7! \Rightarrow M = 5 + {3^2} = 14\)