Question

Никак не могу разобраться..вычислить

Answer 1

0,7^12·0.7^(-15):0.7^(-2) =

= 0,7^12·0.7^(-15)·0.7^2 =

= 0.7^(12-15+2) = 0.7^(-1) = 10/7

Answer 2

$\frac{(0.7)^{12}*(1\frac{3}{7})^{15}}{(\frac{12}{7})^2}=\frac{(0.7)^{12}*(\frac{10}{7})^{15}}{(\frac{10}{7})^2}=(0.7)^{12}*\frac{(\frac{10}{7})^{15}}{(\frac{10}{7})^2}=\\\\=(0.7)^{12}*(\frac{10}{7})^{15-2}=(\frac{7}{10})^{12}*(\frac{10}{7})^{13}=(\frac{10}{7})^{-12}*(\frac{10}{7})^{13}=\\\\=(\frac{10}{7})^{-12+13}=(\frac{10}{7})^1=\frac{10}{7}.$