Bài 1 a) A= 2 $\frac{2}{9}$ . $\frac{1}{3}$ + √(- $\frac{5}{18}$ ) ² - (- $\frac{5}{6}$ ) ² + |-1 $\frac{1}{3}$ | b) B= -2^10 . 3^10 . 6^9 / 4^3 . (-6) ^19
2 câu trả lời
Đáp án:
${\rm a)}\,A=2\dfrac29\!\cdot\!\dfrac13+\sqrt{\left(\dfrac{-5}{18}\right)^2}-\left(\dfrac{-5}6\right)^2+\left|-1\dfrac13\right|\\\Rightarrow A=\dfrac{20}9\!\cdot\!\dfrac13+\left|\dfrac{-5}{18}\right|-\dfrac{25}{36}+\left|\dfrac{-4}3\right|\\\Rightarrow A=\dfrac{20}{27}+\dfrac5{18}-\dfrac{25}{36}+\dfrac43\\\Rightarrow A=\dfrac{20}{27}+\dfrac43+\dfrac5{18}-\dfrac{25}{36}\\\Rightarrow A=\dfrac{56}{27}+\dfrac{-5}{12}\\\Rightarrow A=\dfrac{179}{108}\\{\rm b)}\,B=\dfrac{-2^{10}.3^{10}.6^9}{4^3.\!\left(-6\right)^{19}}\\\Rightarrow B=\dfrac{-\left(2.3\right)^{10}.6^9}{\left(2^2\right)^3.\!\left(-6\right)^{19}}\\\Rightarrow B=\dfrac{-6^{10}.6^9}{2^6.\!\left(-6\right)^{19}}\\\Rightarrow B=\dfrac{-6^{19}}{-6^{19}.64}\\\Rightarrow B=\dfrac1{64}$
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