Bài 1:
a) Ta có:
\(\left(\frac{1}{2}\right)^2 - \frac{25}{17} - (-0,75)\)
\(= \frac{1}{4} - \frac{25}{17} + 0,75\)
\(= \frac{1}{4} - \frac{25}{17} + \frac{3}{4}\)
\(= \frac{1}{4} + \frac{3}{4} - \frac{25}{17}\)
\(= \frac{4}{4} - \frac{25}{17}\)
\(= \frac{17}{17} - \frac{25}{17}\)
\(= -\frac{8}{17}\)
Đáp số: -\(\frac{8}{17}\)
b) Ta có:
\(-\frac{5}{9} - \left(\frac{8}{15} + \frac{4}{9}\right) + \frac{7}{15}\)
\(= -\frac{5}{9} - \frac{8}{15} - \frac{4}{9} + \frac{7}{15}\)
\(= -\frac{5}{9} - \frac{4}{9} - \frac{8}{15} + \frac{7}{15}\)
\(= -\frac{9}{9} - \frac{8}{15} + \frac{7}{15}\)
\(= -1 - \frac{8}{15} + \frac{7}{15}\)
\(= -1 - \frac{1}{15}\)
\(= -\frac{16}{15}\)
Đáp số: -\(\frac{16}{15}\)
c) Ta có:
\(\frac{2}{3} + \frac{1}{3} \cdot \frac{-6}{5}\)
\(= \frac{2}{3} - \frac{6}{15}\)
\(= \frac{2}{3} - \frac{2}{5}\)
\(= \frac{10}{15} - \frac{6}{15}\)
\(= \frac{4}{15}\)
Đáp số: \(\frac{4}{15}\)
Bài 2:
a) Ta có:
\(\frac{5}{2}x + 2 = \frac{3}{2}\)
\(\frac{5}{2}x = \frac{3}{2} - 2\)
\(\frac{5}{2}x = \frac{3 - 4}{2}\)
\(\frac{5}{2}x = -\frac{1}{2}\)
\(x = -\frac{1}{2} \cdot \frac{2}{5}\)
\(x = -\frac{1}{5}\)
Đáp số: \(x = -\frac{1}{5}\)
b) Ta có:
\(\frac{2x - 1}{15} = \frac{7}{3}\)
\(2x - 1 = \frac{7}{3} \cdot 15\)
\(2x - 1 = \frac{7}{3} \cdot \frac{15}{1}\)
\(2x - 1 = \frac{7 \cdot 15}{3 \cdot 1}\)
\(2x - 1 = \frac{105}{3}\)
\(2x - 1 = 35\)
\(2x = 35 + 1\)
\(2x = 36\)
\(x = \frac{36}{2}\)
\(x = 18\)
Đáp số: \(x = 18\)
c) Ta có:
\(3,6 - \frac{5}{4}x = -\frac{1}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - 3,6\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{3,6}{1}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{3,6}{1} \cdot \frac{6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{3,6 \cdot 6}{1 \cdot 6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\frac{5}{4}x = -\frac{1}{6} - \frac{21,6}{6}\)
\(-\