Bài 2.

a) \(\left(-\dfrac{1}{3}\right)^2.\left(-\dfrac{1}{3}\right)=\left(-\dfrac{1}{3}\right)^3=\dfrac{\left(-1\right)^3}{3^3}=-\dfrac{1}{27}\)

b) \(\left(-2\right)^2.\left(-2\right)^3=\left(-2\right)^5=-32\)

c) \(a^5.a^7=a^{12}\)

Bài 3.

a) \(x^2=\dfrac{4}{9}\Leftrightarrow x=\pm\dfrac{2}{3}\)

b) \(x^3=\dfrac{8}{27}\Leftrightarrow x=\dfrac{2}{3}\)

c) \(x^3=-\dfrac{8}{125}\Leftrightarrow x=-\dfrac{2}{5}\)

Bài 1

\(\left(-\dfrac{2}{3}\right)^3=\dfrac{\left(-2\right)^3}{3^3}=-\dfrac{8}{27}\)

\(\left(-1\dfrac{3}{4}\right)^2=\left(-\dfrac{7}{4}\right)^2=\dfrac{\left(-7\right)^2}{4^2}=\dfrac{49}{16}\)

\(\left(-0,1\right)^4=\left(\left(-0,1\right)^2\right)^2=\left(0,01\right)^2=0,0001\)

\(\left(-\dfrac{2}{3}\right)^{2022}:\left(-\dfrac{2}{3}\right)^{2019}=\left(-\dfrac{2}{3}\right)^3=\dfrac{\left(-2\right)^3}{3^3}=-\dfrac{8}{27}\)