Tính đạo hàm của hàm số sau: \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyEaiabg2 % da9iGacogacaGGVbGaai4CamaaCaaaleqabaGaaGOmaaaakmaabmaa % baWaaSaaaeaadaGcaaqaaiaadIhaaSqabaGccqGHRaWkcaaIXaaaba % WaaOaaaeaacaWG4baaleqaaOGaeyOeI0IaaGymaaaaaiaawIcacaGL % Paaaaaa!42E0! y = {\cos ^2}\left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right)\)

\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyEaiaacE % cacqGH9aqpcaaIYaGaaiOlaiGacogacaGGVbGaai4CamaabmaabaWa % aSaaaeaadaGcaaqaaiaadIhaaSqabaGccqGHRaWkcaaIXaaabaWaaO % aaaeaacaWG4baaleqaaOGaeyOeI0IaaGymaaaaaiaawIcacaGLPaaa % caGGUaWaamWaaeaaciGGJbGaai4Baiaacohadaqadaqaamaalaaaba % WaaOaaaeaacaWG4baaleqaaOGaey4kaSIaaGymaaqaamaakaaabaGa % amiEaaWcbeaakiabgkHiTiaaigdaaaaacaGLOaGaayzkaaaacaGLBb % GaayzxaaWaaWbaaSqabeaacaGGVaaaaOGaeyypa0JaeyOeI0IaaGOm % aiaac6caciGGJbGaai4BaiaacohadaqadaqaamaalaaabaWaaOaaae % aacaWG4baaleqaaOGaey4kaSIaaGymaaqaamaakaaabaGaamiEaaWc % beaakiabgkHiTiaaigdaaaaacaGLOaGaayzkaaGaaiOlaiGacohaca % GGPbGaaiOBamaabmaabaWaaSaaaeaadaGcaaqaaiaadIhaaSqabaGc % cqGHRaWkcaaIXaaabaWaaOaaaeaacaWG4baaleqaaOGaeyOeI0IaaG % ymaaaaaiaawIcacaGLPaaacaGGUaWaaeWaaeaadaWcaaqaamaakaaa % baGaamiEaaWcbeaakiabgUcaRiaaigdaaeaadaGcaaqaaiaadIhaaS % qabaGccqGHsislcaaIXaaaaaGaayjkaiaawMcaamaaCaaaleqabaGa % ai4laaaaaaa!723F! y' = 2.\cos \left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right).{\left[ {\cos \left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right)} \right]^/} = - 2.\cos \left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right).\sin \left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right).{\left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right)^/}\)

\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyEaiaacE % cacqGH9aqpcqGHsislciGGZbGaaiyAaiaac6gadaqadaqaaiaaikda % daWcaaqaamaakaaabaGaamiEaaWcbeaakiabgUcaRiaaigdaaeaada % GcaaqaaiaadIhaaSqabaGccqGHsislcaaIXaaaaaGaayjkaiaawMca % aiaac6cadaqadaqaamaalaaabaWaaOaaaeaacaWG4baaleqaaOGaey % 4kaSIaaGymaaqaamaakaaabaGaamiEaaWcbeaakiabgkHiTiaaigda % aaaacaGLOaGaayzkaaWaaWbaaSqabeaacaGGVaaaaOGaaiOlaaaa!4DB6! y' = - \sin \left( {2\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right).{\left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right)^/}.\)

Tính \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaada % WcaaqaamaakaaabaGaamiEaaWcbeaakiabgUcaRiaaigdaaeaadaGc % aaqaaiaadIhaaSqabaGccqGHsislcaaIXaaaaaGaayjkaiaawMcaam % aaCaaaleqabaGaai4laaaakiabg2da9maalaaabaWaaeWaaeaadaGc % aaqaaiaadIhaaSqabaGccqGHRaWkcaaIXaaacaGLOaGaayzkaaWaaW % baaSqabeaacaGGVaaaaOGaaiOlamaabmaabaWaaOaaaeaacaWG4baa % leqaaOGaeyOeI0IaaGymaaGaayjkaiaawMcaaiabgkHiTmaabmaaba % WaaOaaaeaacaWG4baaleqaaOGaeyOeI0IaaGymaaGaayjkaiaawMca % amaaCaaaleqabaGaai4laaaakiaac6cadaqadaqaamaakaaabaGaam % iEaaWcbeaakiabgUcaRiaaigdaaiaawIcacaGLPaaaaeaadaqadaqa % amaakaaabaGaamiEaaWcbeaakiabgkHiTiaaigdaaiaawIcacaGLPa % aadaahaaWcbeqaaiaaikdaaaaaaOGaeyypa0ZaaSaaaeaacqGHsisl % caaIXaaabaWaaOaaaeaacaWG4baaleqaaOWaaeWaaeaadaGcaaqaai % aadIhaaSqabaGccqGHsislcaaIXaaacaGLOaGaayzkaaWaaWbaaSqa % beaacaaIYaaaaaaakiaac6caaaa!638F! {\left( {\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right)^/} = \frac{{{{\left( {\sqrt x + 1} \right)}^/}.\left( {\sqrt x - 1} \right) - {{\left( {\sqrt x - 1} \right)}^/}.\left( {\sqrt x + 1} \right)}}{{{{\left( {\sqrt x - 1} \right)}^2}}} = \frac{{ - 1}}{{\sqrt x {{\left( {\sqrt x - 1} \right)}^2}}}.\)

\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyEaiaacE % cacqGH9aqpdaWcaaqaaiaaigdaaeaadaGcaaqaaiaadIhaaSqabaGc % daqadaqaamaakaaabaGaamiEaaWcbeaakiabgkHiTiaaigdaaiaawI % cacaGLPaaadaahaaWcbeqaaiaaikdaaaaaaOGaaiOlaiGacohacaGG % PbGaaiOBamaabmaabaGaaGOmaiaac6cadaWcaaqaamaakaaabaGaam % iEaaWcbeaakiabgUcaRiaaigdaaeaadaGcaaqaaiaadIhaaSqabaGc % cqGHsislcaaIXaaaaaGaayjkaiaawMcaaiaac6caaaa!4CA2! y' = \frac{1}{{\sqrt x {{\left( {\sqrt x - 1} \right)}^2}}}.\sin \left( {2.\frac{{\sqrt x + 1}}{{\sqrt x - 1}}} \right).\)