Tập xác định của hàm số \(y=\frac{3 x-1}{\sqrt{-4 x+3}}\)
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Lời giải:
Báo saiĐKXĐ:
\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfKttLearuGlw5gvP1wzaeXatLxBI9gBam % XvP5wqSXMqHnxAJn0BKvguHDwzZbqegm0B1jxALjhiov2DaeHbuLwB % Lnhiov2DGi1BTfMBaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFf % euY-Hhbbf9v8qqaqFr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9 % q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqaba % WaaqaafaaakqaabeqaaiabgkHiTiabisda0iabdIha4jabgUcaRiab % iodaZiabg6da+iabicdaWaqaaiabgsDiBlabgkHiTiabisda0iabdI % ha4jabg6da+iabgkHiTiabiodaZaqaaiabgsDiBlabdIha4jabgYda % 8maalaaabaGaeyOeI0IaeG4mamdabaGaeyOeI0IaeGinaqdaaaqaai % abgsDiBlabdIha4jabgYda8maalaaabaGaeG4mamdabaGaeGinaqda % aaaaaa!5A4E! \begin{array}{l} - 4x + 3 > 0\\ \Leftrightarrow - 4x > - 3\\ \Leftrightarrow x < \frac{{ - 3}}{{ - 4}}\\ \Leftrightarrow x < \frac{3}{4} \end{array}\)
Vậy \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfKttLearuGlw5gvP1wzaeXatLxBI9gBam % XvP5wqSXMqHnxAJn0BKvguHDwzZbqegm0B1jxALjhiov2DaeHbuLwB % Lnhiov2DGi1BTfMBaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFf % euY-Hhbbf9v8qqaqFr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9 % q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqaba % WaaqaafaaakeaacqWGebarcqGH9aqpdaqadaqaaiabgkHiTiabg6Hi % LkabcUda7maalaaabaGaeG4mamdabaGaeGinaqdaaaGaayjkaiaawM % caaaaa!43F2! D = \left( { - \infty ;\frac{3}{4}} \right)\) hay \(D=\mathbb{R} \backslash\left[\frac{3}{4},+\infty\right)\)