Cho hàm số \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaWG5bGaeyypa0Jaci4CaiaacMgacaGGUbWdamaaCaaaleqabaWd % biaaikdaaaGccaWG4baaaa!3CFE! y = {\sin ^2}x\). Vi phân của hàm số là:
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeizaiaadM % hacqGH9aqpcaqGKbWaaeWaaeaaciGGZbGaaiyAaiaac6gadaahaaWc % beqaaiaaikdaaaGccaWG4baacaGLOaGaayzkaaGaeyypa0ZaaeWaae % aaciGGZbGaaiyAaiaac6gadaahaaWcbeqaaiaaikdaaaGccaWG4baa % caGLOaGaayzkaaWaaWbaaSqabeaakiadacUHYaIOaaGaaeizaiaadI % hacaaMc8Uaeyypa0JaaGPaVlGacogacaGGVbGaai4CaiaadIhacaGG % UaGaaGOmaiGacohacaGGPbGaaiOBaiaadIhacaqGKbGaamiEaiaayk % W7cqGH9aqpciGGZbGaaiyAaiaac6gacaaIYaGaamiEaiaabsgacaWG % 4baaaa!648A! {\rm{d}}y = {\rm{d}}\left( {{{\sin }^2}x} \right) = {\left( {{{\sin }^2}x} \right)^\prime }{\rm{d}}x\, = \,\cos x.2\sin x{\rm{d}}x\, = \sin 2x{\rm{d}}x\)