Cho hàm số \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaWG5bGaeyypa0JaamOza8aadaqadaqaa8qacaWG4baapaGaayjk % aiaawMcaa8qacqGH9aqpciGGZbGaaiyAaiaac6gapaGaaiika8qacq % aHapaCciGGZbGaaiyAaiaac6gacaWG4bWdaiaacMcaaaa!46BD! y = f\left( x \right) = \sin (\pi \sin x)\). Giá trị \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmOzayaafa % WaaeWaaeaadaWcaaqaaiabec8aWbqaaiaaiAdaaaaacaGLOaGaayzk % aaaaaa!3B00! f'\left( {\frac{\pi }{6}} \right)\) bằng:
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmyEayaafa % Gaeyypa0Jaaiikaiabec8aWjaac6caciGGZbGaaiyAaiaac6gacaWG % 4bGabiykayaafaGaaiOlaiGacogacaGGVbGaai4CaiaacIcacqaHap % aCcaGGUaGaci4CaiaacMgacaGGUbGaamiEaiaacMcacqGH9aqpcqaH % apaCcaGGUaGaci4yaiaac+gacaGGZbGaamiEaiaac6caciGGJbGaai % 4BaiaacohacaGGOaGaeqiWdaNaaiOlaiGacohacaGGPbGaaiOBaiaa % dIhacaGGPaaaaa!5D36! y' = (\pi .\sin x)'.\cos (\pi .\sin x) = \pi .\cos x.\cos (\pi .\sin x)\)
\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyO0H4Tabm % yEayaafaWaaeWaaeaadaWcaaqaaiabec8aWbqaaiaaiAdaaaaacaGL % OaGaayzkaaGaeyypa0JaeqiWdaNaaiOlaiGacogacaGGVbGaai4Cam % aalaaabaGaeqiWdahabaGaaGOnaaaacaGGUaGaci4yaiaac+gacaGG % ZbWaaeWaaeaacqaHapaCcaGGUaGaci4CaiaacMgacaGGUbWaaSaaae % aacqaHapaCaeaacaaI2aaaaaGaayjkaiaawMcaaiabg2da9iabec8a % Wjaac6cadaWcaaqaamaakaaabaGaaG4maaWcbeaaaOqaaiaaikdaaa % GaaiOlaiGacogacaGGVbGaai4CamaabmaabaGaeqiWdaNaaiOlamaa % laaabaGaaGymaaqaaiaaikdaaaaacaGLOaGaayzkaaGaeyypa0ZaaS % aaaeaadaGcaaqaaiaaiodaaSqabaGccaGGUaGaeqiWdahabaGaaGOm % aaaacaGGUaGaci4yaiaac+gacaGGZbWaaSaaaeaacqaHapaCaeaaca % aIYaaaaiabg2da9iaaicdaaaa!6E40! \Rightarrow y'\left( {\frac{\pi }{6}} \right) = \pi .\cos \frac{\pi }{6}.\cos \left( {\pi .\sin \frac{\pi }{6}} \right) = \pi .\frac{{\sqrt 3 }}{2}.\cos \left( {\pi .\frac{1}{2}} \right) = \frac{{\sqrt 3 .\pi }}{2}.\cos \frac{\pi }{2} = 0\)