\(\dfrac{\left(-5\right)^2.20^2}{8^2.125}=\dfrac{\left[\left(-5\right).20\right]^2}{2^{3^2}.5^3}=\dfrac{\left(-100\right)^2}{\text{4^3}.5^3}=\dfrac{10000}{\left(4.5\right)^3}=\dfrac{10000}{20^3}\dfrac{10000}{8000}=\dfrac{5}{4}\)
\(\left\{\left[\left(2\sqrt{2}\right)^2:2,4\right]X\left[5,25:\left(\sqrt{7}\right)^2\right]\right\}\) : \(\left\{\left[2\dfrac{1}{7}:\dfrac{\left(\sqrt{5}\right)^2}{7}\right]:\left[2^2:\dfrac{\left(2\sqrt{2}\right)^2}{\sqrt{81}}\right]\right\}\)
b, tìm x, y, z thoả mãn đẳng thức
\(\sqrt{\left(x-\sqrt{2}\right)^2}\) + \(\sqrt{\left(y+\sqrt{2}\right)^2}\) + |x + y + z| = 0
thực hiện phép tính
a)\(\left(\dfrac{9}{25}-2,18\right):\left(3\dfrac{4}{5}+0,2\right)\)
b)\(\dfrac{3}{8}.19\dfrac{1}{3}-\dfrac{3}{8}.33\dfrac{1}{3}\)
c)\(1\dfrac{4}{23}+\dfrac{5}{21}-\dfrac{4}{23}+0,5+\dfrac{16}{21}\)
d)\(\dfrac{2^{12}.3^5-4^6.81}{2^2.3^6+8^4.3^5}\)
e)\(4\left(-\dfrac{1}{2}\right)^2-2.\left(\dfrac{-1}{2}\right)^2+3.\left(\dfrac{-1}{2}\right)+1\)
g)\(\sqrt{\dfrac{4}{81}}:\sqrt{\dfrac{25}{81}}-1\dfrac{2}{5}\)
Thực hiện phép tính: \(\dfrac{20^3.\left(-49\right)^2}{14^3.5^4}\)
Thực hiện phép tính
\(A=16\dfrac{2}{7}:\left(\dfrac{-3}{5}\right)-28\dfrac{2}{7}:\left(\dfrac{-3}{5}\right)\)
\(C=\left(\dfrac{3}{4}\right)^2-\left(\dfrac{7}{8}+3\right)+2.\left|\dfrac{-5}{8}\right|\)
a, cho A = \(\dfrac{\sqrt{x+1}}{\sqrt{x-3}}\). tìm x để A có giá trị nguyên ( x ϵ Z)
b, Thực hiện phép tính: {[(2\(\sqrt{2}\))\(^2\) : 2,4] x [5,25 : (\(\sqrt{7}\))\(^2\)]} : {[2\(\dfrac{1}{7}\) : \(\dfrac{\left(\sqrt{5}\right)^2}{7}\)] : [2\(^2\) : \(\dfrac{\left(2\sqrt{2}\right)^2}{\sqrt{81}}\)]}
Thực hiện phép tính sau một cách hợp lý:
\(B=\dfrac{\dfrac{5}{9}+\dfrac{5}{13}-\dfrac{5}{23}}{\dfrac{8}{9}+\dfrac{8}{13}-\dfrac{8}{23}}.\dfrac{\dfrac{8}{17}-\dfrac{8}{123}+\dfrac{8}{111}}{\dfrac{5}{17}-\dfrac{5}{123}+\dfrac{5}{111}}\)
Thực hiện phép tính
\(\dfrac{4}{9}:\left(\dfrac{-1}{7}\right)+6\dfrac{5}{9}.\left(\dfrac{2}{3}\right)\)
\(\left(\dfrac{-1}{3}\right)^2.\dfrac{4}{11}+\dfrac{7}{11}.\left(\dfrac{-1}{3}\right)^2\)
Câu 2.Thực hiện phép tính:
a) \(\left(\dfrac{-1}{7}\right)^0-2\dfrac{4}{9}.\left(\dfrac{2}{3}\right)^2\)
b)\(\left(\dfrac{1}{3}-\dfrac{5}{6}\right)^2+\dfrac{5}{6}:2\)
Bài 1 : Thực hiện phép tính :
\(S=\dfrac{21^2\cdot3^5-4^6\cdot9^2}{\left(2^2\cdot3\right)^6+8^4\cdot3^5}-\dfrac{5^{10}\cdot7^3-25^5\cdot49^2}{\left(125\cdot7\right)^3\cdot5^0\cdot14^3}\).
Bài 2 : Tìm x :
ɑ) \(2^{x-1}+5\cdot2^{x-2}=\dfrac{7}{32}\). b) \(\left|x\left(x^2-\dfrac{5}{4}\right)\right|=x\).
