Question

help ............ ...​

Answer 1

$2)\ \ 0,8a^{-6}b^4\cdot 5\, a^{12}\, b^{-4}=4\, a^{6}\, b^0=4a^6\\\\3)\ \ 9\cdot 10^{-1}=0,9\ >\ 9\cdot 10^{-3}=0,009\\\\3)\ \ 2,3\cdot 10^2\\\\5)\ \ y=-\dfrac{3}{x}\ \ ,\\\\a)\ \ x=-1:\ \ y(-1)=-\dfrac{3}{-1}=3\\\\b)\ \ y=1:\ \ 1=-\dfrac{3}{x}\ \ ,\ \ \ x=-3\\\\c)\ \ D(\, -1\, ;\, 3\, )$

$6)\ \ \Big(-\dfrac{x^3}{y^5}\Big)^{-4}\cdot \Big(\dfrac{2y^6}{x^4}\Big)^{-2}=\Big(-\dfrac{y^5}{x^3}\Big)^4\cdot \Big(\dfrac{x^4}{2y^6}\Big)^2=\dfrac{y^{20}}{x^{12}}\cdot \dfrac{x^8}{4y^{12}}=\dfrac{y^8}{4\, x^4}$