Cho \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOzamaabm % aabaGaamiEaaGaayjkaiaawMcaaiabg2da9maalaaabaGaaGymaaqa % aiaadIhaaaGaey4kaSYaaSaaaeaacaaIXaaabaWaaOaaaeaacaWG4b % aaleqaaaaakiabgUcaRiaadIhadaahaaWcbeqaaiaaikdaaaaaaa!41C9! f\left( x \right) = \frac{1}{x} + \frac{1}{{\sqrt x }} + {x^2}\) . Tính f'(1)
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOzaiaacE % cadaqadaqaaiaadIhaaiaawIcacaGLPaaacqGH9aqpdaqadaqaamaa % laaabaGaaGymaaqaaiaadIhaaaGaey4kaSYaaSaaaeaacaaIXaaaba % WaaOaaaeaacaWG4baaleqaaaaakiabgUcaRiaadIhadaahaaWcbeqa % aiaaikdaaaaakiaawIcacaGLPaaadaahaaWcbeqaaiaac+caaaGccq % GH9aqpcqGHsisldaWcaaqaaiaaigdaaeaacaWG4bWaaWbaaSqabeaa % caaIYaaaaaaakiabgkHiTmaalaaabaWaaeWaaeaadaGcaaqaaiaadI % haaSqabaaakiaawIcacaGLPaaadaahaaWcbeqaaiaac+caaaaakeaa % caWG4baaaiabgUcaRiaaikdacaWG4bGaeyypa0JaeyOeI0YaaSaaae % aacaaIXaaabaGaamiEamaaCaaaleqabaGaaGOmaaaaaaGccqGHsisl % daWcaaqaaiaaigdaaeaacaaIYaGaamiEamaakaaabaGaamiEaaWcbe % aaaaGccqGHRaWkcaaIYaGaamiEaaaa!5DA5! f'\left( x \right) = {\left( {\frac{1}{x} + \frac{1}{{\sqrt x }} + {x^2}} \right)^/} = - \frac{1}{{{x^2}}} - \frac{{{{\left( {\sqrt x } \right)}^/}}}{x} + 2x = - \frac{1}{{{x^2}}} - \frac{1}{{2x\sqrt x }} + 2x\)
\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOzaiaacE % cadaqadaqaaiaaigdaaiaawIcacaGLPaaacqGH9aqpcqGHsislcaaI % XaGaeyOeI0YaaSaaaeaacaaIXaaabaGaaGOmaaaacqGHRaWkcaaIYa % Gaeyypa0ZaaSaaaeaacaaIXaaabaGaaGOmaaaaaaa!431A! f'\left( 1 \right) = - 1 - \frac{1}{2} + 2 = \frac{1}{2}\)