\(9^{x-1}=\dfrac{1}{\sqrt{81}}\Leftrightarrow9^{x-1}=\dfrac{1}{9}=9^{-1}\Rightarrow x-1=-1\Rightarrow x=0\)
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Tìm x:
a) \(\dfrac{x}{-9}=\dfrac{-40}{45}\)
b) \(\left|2x+\dfrac{1}{3}\right|+\dfrac{4}{9}=-5+\sqrt{\dfrac{16}{81}}\)
Tìm x:
a) \(\dfrac{16}{3}:x=\dfrac{50}{12}\left(-0,06\right)\) b) \(2.x-1^3=-8\) c) \(\dfrac{\left(0.8\right)^5}{\left(0.4\right)^6}=x\)
d)\(0,944-2.x=3,268\) e)\(\sqrt{\dfrac{0,09}{25}=-\dfrac{4,7}{5}+x}\) g)\(\sqrt{5^2-3^2}=-\sqrt{81-x}\)
1.Tìm x biết rằng:
\(\sqrt{\left(\dfrac{1}{3}+x\right)^2}:\left(x+\dfrac{3}{4}\right)=\dfrac{7}{9}\)
Tìm x,y,z
a) \(\sqrt{3-x}=5\)
b) \(\left(x+\dfrac{1}{2}\right)^2=\dfrac{81}{64}\)
c) \(\dfrac{x}{2}=\dfrac{y}{3}=\dfrac{z}{5}\)và \(x^2-2y^2+z^2=44\)
d) \(\left(x-0,2\right)^{70}+\left(y+3,1\right)^{20}=0\)
tìm x
a, \(1\dfrac{2}{3}x-\dfrac{1}{4}=\dfrac{5}{6}\)
b, \(\dfrac{x}{-4}=\dfrac{-48}{3x}\)
c, \(3^{2.x+1}=81\)
Tìm x, biết
a.dfrac{2}{3}x-dfrac{1}{2}x (dfrac{-7}{12}) . dfrac{7}{5}
b.(dfrac{1}{5} - dfrac{3}{2}x)^2 dfrac{9}{4}
c. (1,25 - dfrac{4}{5}x)^3 -125
d. 2^x + 2^{x+4} 544
e.dfrac{3}{4}x - 4,5+ dfrac{4}{5}x 3
g. left|3x-2right| left|2x-3right|
h.(x2 -4)sqrt{x} 0
i. (dfrac{1}{3}x - 4 )2 dfrac{16}{25}
j.4x2 -1 0
k.2x2+0,82 1
l.dfrac{5}{12}sqrt{x} - dfrac{1}{6} dfrac{1}{3}
m.(sqrt{x-1} + 5)(x-6sqrt{x} 0
Đọc tiếp
Tìm x, biết
a.\(\dfrac{2}{3}\)x-\(\dfrac{1}{2}\)x = (\(\dfrac{-7}{12}\)) . \(\dfrac{7}{5}\)
b.(\(\dfrac{1}{5}\) - \(\dfrac{3}{2}\)x)\(^2\) = \(\dfrac{9}{4}\)
c. (1,25 - \(\dfrac{4}{5}\)x)\(^3\) = -125
d. 2\(^x\) + 2\(^{x+4}\) = 544
e.\(\dfrac{3}{4}\)x - 4,5+ \(\dfrac{4}{5}\)x = 3
g. \(\left|3x-2\right|\) =\(\left|2x-3\right|\)
h.(x2 -4)\(\sqrt{x}\) = 0
i. (\(\dfrac{1}{3}\)x - 4 )2 = \(\dfrac{16}{25}\)
j.4x2 -1 = 0
k.2x2+0,82 =1
l.\(\dfrac{5}{12}\)\(\sqrt{x}\) - \(\dfrac{1}{6}\) = \(\dfrac{1}{3}\)
m.(\(\sqrt{x-1}\) + 5)(x-6\(\sqrt{x}\) = 0
\(A=\dfrac{\sqrt{x}+1}{\sqrt{x}-1}\)
Thực hiện phép tính:(hợp lý nếu có thể)
a, 5.dfrac{5}{27}+dfrac{7}{23}+0,5.dfrac{5}{7}+dfrac{16}{23}+dfrac{1}{2}
b, 25dfrac{1}{6}:dfrac{-4}{5}-45dfrac{1}{6}:dfrac{-4}{5}
c, 25.left(dfrac{-1}{5}right)^3+dfrac{1}{5}-2.left(dfrac{-1}{2}right)^2-dfrac{1}{2}
d, -left(251.3+281right)+3.251-left(1-281right)
e, left(0,75-dfrac{1}{4}right):left(-5right)+dfrac{1}{15}-left(-dfrac{1}{5}right):left(-3right)
f, sqrt{dfrac{4}{81}}:sqrt{dfrac{25}{81}}-1dfrac{2}{5}
Đọc tiếp
Thực hiện phép tính:(hợp lý nếu có thể)
a, \(5.\dfrac{5}{27}+\dfrac{7}{23}+0,5.\dfrac{5}{7}+\dfrac{16}{23}+\dfrac{1}{2}\)
b, \(25\dfrac{1}{6}:\dfrac{-4}{5}-45\dfrac{1}{6}:\dfrac{-4}{5}\)
c, \(25.\left(\dfrac{-1}{5}\right)^3+\dfrac{1}{5}-2.\left(\dfrac{-1}{2}\right)^2-\dfrac{1}{2}\)
d, \(-\left(251.3+281\right)+3.251-\left(1-281\right)\)
e, \(\left(0,75-\dfrac{1}{4}\right):\left(-5\right)+\dfrac{1}{15}-\left(-\dfrac{1}{5}\right):\left(-3\right)\)
f, \(\sqrt{\dfrac{4}{81}}:\sqrt{\dfrac{25}{81}}-1\dfrac{2}{5}\)
a) [2^{-2} + 0,75] . 3dfrac{3}{5} - sqrt{dfrac{36}{25}} : left(-1dfrac{4}{5}right) + 4 . left(-dfrac{1}{2015}right)^0
b) left(-dfrac{3}{5}right)^2 . left(0,6-left|dfrac{1}{2}-dfrac{1}{5}right|right) - sqrt{left(dfrac{-3}{8}right)^2} : 1dfrac{1}{8}
c) sqrt{0,49} : sqrt{dfrac{16}{25}} + sqrt{dfrac{4}{81}} : sqrt{dfrac{25}{81}} - left(-dfrac{1}{2}right)^3
d) 19dfrac{1}{3} : dfrac{7}{3} - 33dfrac{1}{3} : dfrac{7}{3} - left|-dfrac{2}{7}right|
e) dfrac{4^6.9^5+6^9.120}{-6^{11}-8^4.3^{12}}...
Đọc tiếp
a) [\(2^{-2}\) + 0,75] . \(3\dfrac{3}{5}\) - \(\sqrt{\dfrac{36}{25}}\) : \(\left(-1\dfrac{4}{5}\right)\) + 4 . \(\left(-\dfrac{1}{2015}\right)^0\)
b) \(\left(-\dfrac{3}{5}\right)^2\) . \(\left(0,6-\left|\dfrac{1}{2}-\dfrac{1}{5}\right|\right)\) - \(\sqrt{\left(\dfrac{-3}{8}\right)^2}\) : \(1\dfrac{1}{8}\)
c) \(\sqrt{0,49}\) : \(\sqrt{\dfrac{16}{25}}\) + \(\sqrt{\dfrac{4}{81}}\) : \(\sqrt{\dfrac{25}{81}}\) - \(\left(-\dfrac{1}{2}\right)^3\)
d) \(19\dfrac{1}{3}\) : \(\dfrac{7}{3}\) - \(33\dfrac{1}{3}\) : \(\dfrac{7}{3}\) - \(\left|-\dfrac{2}{7}\right|\)
e) \(\dfrac{4^6.9^5+6^9.120}{-6^{11}-8^4.3^{12}}\)
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