Cách làm cho bạn:
a) Ta có:
53 : (-5)2 = 53 : 52 = 53 – 2 = 5
b) Ta có:
\(\left ( \frac{3}{4} \right )^{5}\): \(\left ( \frac{3}{4} \right )^{3}\) = \(\left ( \frac{3}{4} \right )^{5 -3}\) = \(\left ( \frac{3}{4} \right )^{2}\) = \(\frac{9}{16}\)
c) Ta có
(-12)3 : 83 = -123 : 83= (-4 . 3)3 : (4 . 2)3 = \(\left ( \frac{-4 .3}{4 .2}\right )^{3}\)= \(\left ( -\frac{3}{2} \right )^{3}\)= -\(\frac{27}{8}\)
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