Câu 3. Tìm x, biết:
a) x : $\left (- \frac{1}{2} \right )^{3}$ =$\frac{-1}{2}$
x = $\frac{-1}{2}$ . $\left (- \frac{1}{2} \right )^{3}$
x = $\frac{1}{16}$
b) x . $\left (- \frac{3}{5} \right )^{7}$ = $\left (- \frac{3}{5} \right )^{9}$
x = $\left (- \frac{3}{5} \right )^{9}$ : $\left (- \frac{3}{5} \right )^{7}$
x = $\left (- \frac{3}{5} \right )^{2}$
x = $\frac{9}{25}$
c) $\left ( \frac{-2}{3} \right )^{11}$ : x = $\left ( \frac{-2}{3} \right )^{9}$
x = $\left ( \frac{-2}{3} \right )^{11}$ : $\left ( \frac{-2}{3} \right )^{9}$
x = $\left ( \frac{-2}{3} \right )^{2}$
x = $\frac{4}{9}$
d) x . (0,25)6 = $\left ( \frac{1}{4} \right )^{8}$
x = $\left ( \frac{1}{4} \right )^{8}$ : $\left ( \frac{1}{4} \right )^{6}$
x = $\left ( \frac{1}{4} \right )^{2}$
x = $\frac{1}{16}$