6: \(=\dfrac{2^{20}\left(2^{20}-1+3^{20}\right)}{3^{20}\left(2^{20}-1+3^{20}\right)}=\left(\dfrac{2}{3}\right)^{20}\)
7: \(=\dfrac{7}{3}\left(19+\dfrac{1}{3}-33-\dfrac{1}{3}\right)-\dfrac{2}{7}=\dfrac{7}{3}\cdot\left(-14\right)-\dfrac{2}{7}\)
\(=-\dfrac{98}{3}-\dfrac{2}{7}=-\dfrac{692}{21}\)
8: \(=\dfrac{1}{9}-\left(\dfrac{1}{4}:2+\dfrac{7}{21}\cdot\dfrac{4}{16}\right)\)
\(=\dfrac{1}{9}-\dfrac{1}{8}-\dfrac{1}{12}=-\dfrac{7}{72}\)
10: =(-0,5)^2-17/2+0,5
=0,25+0,5-8,5
=-7,75