1:
\(\dfrac{\dfrac{1}{2}-3,5}{\dfrac{2}{3}-\dfrac{1}{3}.\left(1+\dfrac{1}{4}\right)}\)
2:
a)\(\dfrac{7}{9}.\left(1\dfrac{1}{6}-1:1\dfrac{1}{19}-\dfrac{1}{15}\right)+4\dfrac{2}{5}:24\)
b)\(\left(\dfrac{7}{12}-\dfrac{8}{15}\right)^2+\dfrac{4}{5}.\left(\dfrac{7}{10}-\dfrac{9}{16}\right)\)