\(\dfrac{20^3.\left(-49\right)^2}{14^3.5^4}=\dfrac{2^3.2^3.5^3.7^4}{2^3.7^3.5^4}=\dfrac{2^3.7}{5}=\dfrac{8.7}{5}=\dfrac{56}{5}\)
1) A = \(\left(-\dfrac{25}{27}-\dfrac{31}{42}\right)-\left(\dfrac{-7}{27}-\dfrac{3}{42}\right)\)
2) B = \(\dfrac{10\dfrac{3}{10}-\left(9,5-0,25\times18\right)\div0,5}{1\dfrac{1}{5}-1\dfrac{1}{2}}\)
3) C = \(\dfrac{3}{49}\times\dfrac{19}{2}-\dfrac{3}{49}\times\dfrac{5}{2}-\left(\dfrac{1}{20}-\dfrac{1}{4}\right)^2\times\left(\dfrac{-1}{2}-\dfrac{193}{14}\right)\)
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)\(\sqrt{\dfrac{4}{81}}:\sqrt{\dfrac{25}{81}}-1\dfrac{2}{5}\)
\(\left\{\left[\left(2\sqrt{2}\right)^2:2,4\right]X\left[5,25:\left(\sqrt{7}\right)^2\right]\right\}\) : \(\left\{\left[2\dfrac{1}{7}:\dfrac{\left(\sqrt{5}\right)^2}{7}\right]:\left[2^2:\dfrac{\left(2\sqrt{2}\right)^2}{\sqrt{81}}\right]\right\}\)
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
1) Thực hiện các phép tính : ( tính hợp lí nếu có thể )
a) \(\frac{4^2.3^3.125}{2^3.5^6.27}\) b) ( -0,25 ) : ( \(\frac{1^{ }}{2}\)) \(^2\)
c) \(\frac{2^3.\sqrt{64}.10^6}{\left(2^4\right)^3.5^5}\) d) \(\frac{6^2.4^3.10^4}{2^6.5^4.16}\)
e) \(40:\left\{\left[11+\left(26-3^3\right)\right]^{ }.2\right\}\)
f) \(\left[\left(-5,2\right)+\left(-7,8\right)\right]+\left(4,9\right)+7,8\)
g) \(\left\{\left[11+\left(4^2-2^5\right)\right].2\right\}.\sqrt{49}\)
h) (-15).0,23 + (-15) .0,77
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
\(\dfrac{4}{9}:\left(\dfrac{-1}{7}\right)+6\dfrac{5}{9}.\left(\dfrac{2}{3}\right)\)
\(\left(\dfrac{-1}{3}\right)^2.\dfrac{4}{11}+\dfrac{7}{11}.\left(\dfrac{-1}{3}\right)^2\)
tính hợp lý
a, A = \(\dfrac{1-\dfrac{1}{\sqrt{49}}+\dfrac{1}{49}-\dfrac{1}{\left(7\sqrt{7}\right)^2}}{\dfrac{\sqrt{64}}{2}-\dfrac{4}{7}+\left(\dfrac{2}{7}\right)^2-\dfrac{4}{343}}\)
b, M = 1 - \(\dfrac{5}{\sqrt{196}}\) - \(\dfrac{5}{\left(2\sqrt{21}\right)^2}\) - \(\dfrac{\sqrt{25}}{204}\) - \(\dfrac{\left(\sqrt{5}\right)^2}{374}\)
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, \(\left(18\dfrac{1}{3}:\sqrt{225}+8\dfrac{2}{3}.\sqrt{\dfrac{49}{4}}\right)\): \(\left[\left(12\dfrac{1}{3}+8\dfrac{6}{7}\right)-\dfrac{\left(\sqrt{7}\right)^2}{\left(3\sqrt{2}\right)^2}\right]\): \(\dfrac{1704}{445}\)
b, \(\dfrac{1}{1.2}\)+\(\dfrac{1}{2.3}\)+...+\(\dfrac{1}{99.100}\)
c, \(\left(1-\dfrac{1}{2}\right)\)x\(\left(1-\dfrac{1}{3}\right)\)x.....x\(\left(1-\dfrac{1}{n+1}\right)\) (n ϵ N)
d, -66 x \(\left(\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{11}\right)\) + 124 x -37 + 63 x -124
e, \(\dfrac{7}{4}\) x \(\left(\dfrac{33}{12}+\dfrac{3333}{2020}+\dfrac{333333}{303030}+\dfrac{33333333}{42424242}\right)\)
