Odpowiedź:
[tex]a)\ \ 84^3:21^3=(84:21)^3=4^3=64\\\\\\b)\ \ (2\frac{1}{3})^{10}\cdot(\frac{3}{7})^{10}=(2\frac{1}{3}\cdot\frac{3}{7})^{10}=(\frac{\not7^1}{\not3_{1}}\cdot\frac{\not3^1}{\not7_{1}})^{10}=1^{10}=1\\\\\\c)\ \ \dfrac{5^8\cdot2^9}{10^7}=\dfrac{5^8\cdot2^9}{2^7\cdot5^7}=5^{8-7}\cdot2^{9-7}=5^1\cdot2^2=5\cdot4=20[/tex]
