Hàm số \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyEaiabg2 % da9maabmaabaGaaGymaiabgUcaRiGacohacaGGPbGaaiOBaiaadIha % aiaawIcacaGLPaaadaqadaqaaiaaigdacqGHRaWkciGGJbGaai4Bai % aacohacaWG4baacaGLOaGaayzkaaaaaa!45E8! y = \left( {1 + \sin x} \right)\left( {1 + \cos x} \right)\) có đạo hàm là:
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyEaiabg2 % da9maabmaabaGaaGymaiabgUcaRiGacohacaGGPbGaaiOBaiaadIha % aiaawIcacaGLPaaadaqadaqaaiaaigdacqGHRaWkciGGJbGaai4Bai % aacohacaWG4baacaGLOaGaayzkaaGaeyypa0JaaGymaiabgUcaRiGa % cohacaGGPbGaaiOBaiaadIhacqGHRaWkciGGJbGaai4Baiaacohaca % WG4bGaey4kaSIaci4CaiaacMgacaGGUbGaamiEaiaac6caciGGJbGa % ai4BaiaacohacaWG4bGaeyypa0JaaGymaiabgUcaRiGacohacaGGPb % GaaiOBaiaadIhacqGHRaWkciGGJbGaai4BaiaacohacaWG4bGaey4k % aSYaaSaaaeaacaaIXaaabaGaaGOmaaaaciGGZbGaaiyAaiaac6gaca % aIYaGaamiEaaaa!6C6F! y = \left( {1 + \sin x} \right)\left( {1 + \cos x} \right) = 1 + \sin x + \cos x + \sin x.\cos x = 1 + \sin x + \cos x + \frac{1}{2}\sin 2x\)
Suy ra \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabmyEayaafa % Gaeyypa0Jaci4yaiaac+gacaGGZbGaamiEaiabgkHiTiGacohacaGG % PbGaaiOBaiaadIhacqGHRaWkciGGJbGaai4BaiaacohacaaIYaGaam % iEaaaa!4603! y' = \cos x - \sin x + \cos 2x\)