----- Nội dung ảnh ----- B/TỦ LUẬN Câu 1: Tính a) \(\left| \frac{1}{2} - \frac{3}{4} \right| \) b) \( \left| \frac{9}{12} - \frac{15}{21} \right| \) c) \( 0,125 : \left( -\frac{8}{35} \right) \) d) \( 0,2 - \left( -\frac{1}{2} \right) \) e) \( \sqrt{-3} - 3 \) f) \(- \sqrt{8} \cdot 0.5\)
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5 Tham khảo câu trả lời từ Trợ lý ảo Lazi To solve the expressions in the image, let's tackle each part step by step: ### a) \[ \left( \frac{-5}{3} + \frac{1}{4} \right) \cdot \left( \frac{12}{5} - \frac{1}{2} \right) \] 1. Find a common denominator: - For \(-\frac{5}{3} + \frac{1}{4}\): common denominator is 12. - \(-\frac{5}{3} = -\frac{20}{12}\) and \(\frac{1}{4} = \frac{3}{12}\). - So, \(-\frac{20}{12} + \frac{3}{12} = -\frac{17}{12}\). 2. For \(\frac{12}{5} - \frac{1}{2}\): - Common denominator is 10. - \(\frac{12}{5} = \frac{24}{10}\) and \(-\frac{1}{2} = -\frac{5}{10}\). - So, \(\frac{24}{10} - \frac{5}{10} = \frac{19}{10}\). 3. Now multiply: \[ -\frac{17}{12} \cdot \frac{19}{10} = -\frac{323}{120} \] ### b) \[ -\frac{1}{15} + \frac{9}{21} + \left(-\frac{14}{15}\right) + \frac{12}{21} + 2 \] 1. Convert to common denominators: - For \(-\frac{1}{15} - \frac{14}{15}\): result is \(-\frac{15}{15} = -1\). - Combine: - \(\frac{9}{21} + \frac{12}{21} = \frac{21}{21} = 1\). - So, \(-1 + 1 + 2 = 2\). ### c) \[ 0.125 \cdot \left(-\frac{8}{35}\right) \] 1. Convert \(0.125\) to a fraction: \[ 0.125 = \frac{1}{8} \] 2. Multiply: \[ \frac{1}{8} \cdot -\frac{8}{35} = -\frac{1}{35} \] ### d) \[ 0.2 \cdot \left(-\frac{3}{8} \cdot \frac{1}{5} \cdot \left(-\frac{5}{8}\right)\right) \] 1. Calculate \(-\frac{3}{8} \cdot \frac{1}{5} \cdot \left(-\frac{5}{8}\right)\): - Negative signs cancel. - Result is \(\frac{3 \cdot 5}{8 \cdot 5 \cdot 8} = \frac{15}{320} = \frac{3}{64}\). 2. Multiply by \(0.2\): \[ 0.2 \cdot \frac{3}{64} = \frac{2}{10} \cdot \frac{3}{64} = \frac{6}{640} = \frac{3}{320} \] ### e) \[ \sqrt{(-3)^2} \cdot \frac{2}{3} \cdot \sqrt{8^2} \cdot 0.5 \] 1. Calculate: \(\sqrt{(-3)^2} = 3\), \(\sqrt{8^2} = 8\). 2. Multiply: \[ 3 \cdot \frac{2}{3} \cdot 8 \cdot 0.5 = 2 \cdot 8 \cdot 0.5 = 8 \] ### f) \[ -\left(-\frac{3}{2}\right) \cdot \frac{13}{7} \] 1. Multiply: \[ \frac{3}{2} \cdot \frac{13}{7} = \frac{39}{14} \] In conclusion, the results are: ### Answers - a) \(-\frac{323}{120}\) - b) \(2\) - c) \(-\frac{1}{35}\) - d) \(\frac{3}{320}\) - e) \(8\) - f) \(\frac{39}{14}\)