Bonsoir,
[tex]A = \frac{\frac{1}{5}-\frac{4}{3}}{\frac{2}{3}+\frac{1}{6}}\\\\A = \frac{\frac{3}{15} - \frac{20}{15}}{\frac{4}{6} + \frac{1}{6}}\\\\A = \frac{\frac{3-20}{15}}{\frac{4+1}{6}}\\\\A = \frac{-\frac{17}{15}}{\frac{5}{6}}\\\\A = -\frac{17}{15}\cdot \frac{6}{5}\\\\A = -\frac{17\cdot 3\cdot 2}{3\cdot5^2}\\\\\boxed{A = -\frac{34}{25}}[/tex]
[tex]B = \frac{4 \cdot 10^{-5} \cdot 10}{12 \cdot (10^2)^{-2}}\\\\B = \frac{2^2 \cdot 10^{-5 + 1}}{2^2\cdot 3\cdot 10^{2\cdot(-2)}}\\\\B = \frac{1}{3}\cdot \frac{10^{-4}}{10^{-4}}\\\\\boxed{B = \frac{1}{3}}[/tex]
Bonne soirée,
Thomas
