\(\dfrac{5^{x+1}}{125}=\dfrac{1}{25^{x-2}}\\ \dfrac{5^{x+1}}{125}=\dfrac{1}{5^{2x-4}}\\ 5^{x+1}\cdot5^{2x-4}=125\\ 5^{x+1+2x-4}=5^3\\ 5^{\left(x+2x\right)+\left(1-4\right)}=5^3\\ 5^{3x-3}=5^3\\ 3x-3=3\\ 3x=6\\ x=2\)
Tìm x, biết:
a) \(\dfrac{2}{3}\)x - \(\dfrac{1}{2}\)x = \(\left(-\dfrac{7}{12}\right)\) . \(1\dfrac{2}{5}\)
b) \(\left(\dfrac{1}{5}-\dfrac{3}{2}x\right)^2\) = \(\dfrac{9}{4}\)
c) (1,25 - \(\dfrac{4}{5}\)x)3 = -125
Tìm x, biết:
a) \(\dfrac{3}{7}\)x - \(\dfrac{2}{3}\)x = \(\dfrac{10}{21}\)
b) \(\dfrac{7}{35}\) : (x - \(\dfrac{1}{3}\)) = \(-\dfrac{2}{25}\)
c) 3.(x - \(\dfrac{1}{2}\)) - 5. (x + \(\dfrac{3}{5}\)) = -x + \(\dfrac{1}{5}\)
Thực hiện pháp tính :
25.(\(\dfrac{-1}{5}\)) + \(\dfrac{1}{5}\) - 2 . (\(\dfrac{-1}{2}\))\(^2\) - \(\sqrt{\dfrac{1}{4}}\)
Tìm x :
6 - | \(\dfrac{1}{2}\) - x | = \(\dfrac{2}{5}\)
a,2.(\(\dfrac{1}{4}\)+x)\(^3\)=(\(-\dfrac{27}{4}\))
b,(x+\(\dfrac{1}{2}\))\(^3\):3=\(\dfrac{-1}{81}\)
c,(\(\dfrac{2}{3}\)-x)\(^2\)=1:\(\dfrac{4}{9}\)
d,(2x-\(\dfrac{1}{5}\))\(^2\)+\(\dfrac{16}{25}\)=1
e,(\(\dfrac{2}{5}\)-3x)\(^2\)-\(\dfrac{1}{5}\)=\(\dfrac{4}{25}\)
a \(\dfrac{-4}{7}\) - \(\dfrac{5}{13}\) x \(\dfrac{-39}{25}\) + \(\dfrac{-1}{42}\) : \(\dfrac{-5}{6}\)
b \(\dfrac{2}{9}\) x [\(\dfrac{4}{45}\): ( \(\dfrac{1}{5}\) - \(\dfrac{2}{15}\)) + 1\(\dfrac{2}{3}\)] - \(\dfrac{-5}{27}\)
Câu 1: Thực hiện phép tính
a, \(40\dfrac{1}{4}:\dfrac{5}{7}-25\dfrac{1}{4}:\dfrac{5}{7}-\dfrac{1}{2021}\)
b, \(\left|\dfrac{-5}{9}\right|.\sqrt{81}-2021^0.\dfrac{16}{25}\)
Câu 2: Tìm x
\(3\left(x-\dfrac{1}{3}\right)-7\left(x+\dfrac{3}{7}\right)=-2x+\dfrac{1}{3}\)
tính giá trị lớn nhất của
A = -( x + 1 ) \(^2\)+ 5
tìm x
2. x - 0, 7 = 1, 3
x - √25 = \(\left(\dfrac{2}{5}-\dfrac{6}{5}\right)\)
\(\dfrac{3}{4}+\dfrac{1}{4}\) : x = \(\dfrac{2}{5}\)
Câu 1: Tìm x, biết:
a)\(x^2-\dfrac{16}{25}=0\) b)\(\dfrac{2}{5}-\left|\dfrac{1}{2}-x\right|=6\)
C2.Tính giá của biểu thức:
a)\(A=1\dfrac{5}{13}-0,25-\left(2\dfrac{5}{9}+\dfrac{18}{13}-\dfrac{1}{4}\right)\)
b)\(\dfrac{\dfrac{3}{5}.7^2-3.5^6+\dfrac{3}{5}.3^9}{\dfrac{3}{4}.7^2-\dfrac{3}{4}.5^7+\dfrac{3}{4}.3^9}\)
a)x-\(\dfrac{2}{3}=\dfrac{8}{7}\)
b)\(\left(x+\dfrac{1}{3}\right)=\dfrac{4}{25}\)
c)\(-\dfrac{2}{3}\div x+\dfrac{5}{8}=-\dfrac{7}{12}\)
